Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study
View Article PDF
Lung cancer is the commonest cause of cancer death in Aotearoa New Zealand.[[1]] Most patients with non-small cell lung cancer (NSCLC) will have advanced disease at diagnosis. The prognosis for these patients is poor with an estimated historical 5-year survival of less than 10%.[[2,3]] Indeed, the 5-year overall survival for lung cancer across all stages in Aotearoa New Zealand in 2014 was only 15.5%, with just a 4% improvement from 1999.[[4]] Of particular concern has been the finding that Māori, the Indigenous people of Aotearoa New Zealand , have a 30% greater mortality from lung cancer compared to non-Māori.[[3]] Previous research has revealed ethnic disparity in cancer treatment—for instance, Māori with breast cancer are less likely to receive radiotherapy or long-term adjuvant endocrine therapy,[[5]] and Māori with colorectal cancer are less likely to receive chemotherapy.[[6–10]] There is scant research into ethnic differences in NSCLC treatment and its impacts on survival outcomes in Aotearoa New Zealand patients; hence, we sought to investigate possible differences in the use of systemic anti-cancer chemotherapy (SACT) in Māori and non-Māori.
Methods
Data source
This is a retrospective study based on a comprehensive dataset collected prospectively using a purpose-built SACT prescribing and database system from 1 January 2000 to 31 December 2021. We obtained patient-level data for individuals with a first diagnosis of advanced NSCLC referred to the Medical Oncology Unit Waikato Hospital. Waikato Hospital is the regional cancer centre for the central region of the North Island of Aotearoa New Zealand and provides care for approximately 800,000 people, of whom 30% identify as Māori. We collected information on the following variables: age, gender, ethnicity (Māori or non-Māori), date/year of lung cancer diagnosis, stage at diagnosis, SACT regimens prescribed and survival. We included only those patients with Stage 3 and 4 NSCLC. We excluded patients enrolled in clinical trials (22) and patients with epidermal growth factor receptor (EGFR) mutated lung cancer (95).
Analysis
We reviewed the characteristics and SACT regimens of lung cancer patients with advanced NSCLC. We investigated ethnic differences in patient factors and SACT regimens in those receiving first and second SACT regimens, and those not receiving SACT. We used Chi-squared tests to compare categorical variables and Student’s t-Tests for continuous variables.
Using the Kaplan–Meier method, we calculated all-cause survival after diagnosis of lung cancer for patients with and without SACT by ethnicity. We also analysed the all-cause survival in those receiving different SACT regimens (carboplatin plus pemetrexed, carboplatin plus gemcitabine, cisplatin plus gemcitabine, carboplatin plus paclitaxel, and other regimens) as their first-line treatments. Using logistic regression models, we examined the odds ratios (OR) of surviving 12 months in the entire cohort, adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. Then, we estimated the OR of surviving 12 months in the group receiving their first SACT regimen adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. OR of receiving first-line SACT or moving from first- to second-line SACT were also calculated, adjusting for age, gender, ethnicity and year of diagnosis. All analyses were carried out using Stata 15 (StataCorp LLC, Texas, United States).
Results
After excluding trial patients (22) and those with EGFR-mutated lung cancer (95), we identified 1,057 cases who had been referred to oncology with advanced-stage NSCLC. Table 1 shows that 562 (53%) were treated with SACT. The key factor associated with the likelihood of receiving SACT was the patient’s age, with older patients being less likely to be treated. Of those with NSCLC, 316/1,057 (30%) had been identified as Māori and there was no difference in the proportion of Māori and non-Māori who received SACT. Māori who received SACT were on average 1 year younger than non-Māori (mean age 62 years compared to 63 years in non-Māori, p=0.04). Non-Māori who did not receive SACT were older than Māori who did not receive SACT (mean 68 vs 61 years, p<0.01). The proportion of referred patients receiving treatment increased from 49% (65/133) in 2000–2004 to 55% (222/401) in 2015–2021 (Table 1). There was also an increase in the proportion receiving a second or subsequent SACT regimen from 11% (15/133) to 16% (64/401).
Table 2 shows the frequency of various regimens used as SACT. Of these, carboplatin plus gemcitabine and carboplatin plus paclitaxel were the most common, accounting for over half the chosen first-line regimens. A total of 166/562 (30%) patients received a second-line SACT regimen. Vinorelbine (51/166, 31%) and docetaxel (38/166, 23%) were the commonest second-line choices.
Of those treated with SACT, median survival for non-Māori was 11.9 months and for Māori 8.5 months. Overall median survival in those not treated was 4.7 months (Table 1). Kaplan–Meier survival analysis (Figure 1) showed that patients with advanced NSCLC had a poor prognosis with a 5-year survival of less than 10%. Outcomes were poorer for Māori in both those treated with and without SACT. Patients not receiving SACT had a 1-year survival of approximately 20%, while patients treated with SACT had a 1-year survival of approximately 40%. After 3 years, there was no difference in survival between those with and without SACT.
View Tables 1–4, Figure 1.
Table 3A demonstrates that patients treated with first-line SACT regimens were 2–3 times significantly more likely to survive 12 months than those not receiving SACT regimens (p<0.001) after adjustment for age, gender, ethnicity and year of diagnosis. As expected, there was no significant difference in survival between different first-line SACT regimens in those receiving SACT (Table 3B). For the entire cohort, non-Māori were 68.8% more likely to survive 12 months than Māori (Table 3A). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori (Table 3B). There was no ethnic difference in the proportion of patients receiving first-line SACT (adjusted OR: 1.096; 95% confidence interval [CI]: 0.833–1.443; p>0.05); however, non-Māori were significantly more likely than Māori to change from a first to a second SACT (adjusted OR: 1.536; 95% CI: 1.015–2.325; p<0.05, Table 4).
Discussion
Our study provides valuable insights into the treatment and survival outcomes of patients with advanced NSCLC based on an Aotearoa New Zealand SACT dataset derived over 20 years. Of patients with advanced NSCLC, 53% received first-line SACT, and 30% had second-line treatment. This proportion of advanced NSCLC patients treated with SACT is higher than in the United Kingdom (40%) but less than that in in Belgium, Norway and Portugal (75%).[[11]] Patients receiving SACT had better survival than those that did not. Median survival of patients treated with first SACT, second SACT and without SACT was 10.7, 17.5 and 4.7 months, respectively. A retrospective study of patients with advanced NSCLC in Portugal showed that patients not receiving SACT had a median survival of 1.8–2.3 months while those treated had a median survival of 10.3–12.6 months.[[12]]
The proportion of Māori and non-Māori patients treated with SACT were 54% and 53% respectively. We found no ethnic difference in receiving first-line SACT treatment. Randomised studies show a modest but statistically significant survival advantage of approximately 2 months for receipt of second-line chemotherapy compared to best supportive care.[[13]] It is therefore noteworthy that we found Māori patients with advanced NSCLC were less likely to receive second-line SACT. In addition, Māori receiving SACT were also less likely to survive 12 months than non-Māori. The reasons underlying ethnic disparities in cancer treatment and outcomes are complex. Social deprivation has a resultant influence on income, employment, housing and access to care, which are known key determinants of health. Over 60% of Māori patients live in localities that fall within the three most deprived deciles of the NZDep2001 Index of Deprivation.[[14]] Additionally, patient-level factors, treatment process factors and health system factors play a part.[[15–18]] As an example of patient-level factors, Māori are more likely to have comorbidities than non-Māori.[[17]] It has been reported that compared to non-Māori, Māori have a greater tendency to decline treatment,[[19]] but our study did not show a difference in uptake of first-line SACT. This may, however, be a factor in the lower transition to second-line SACT. As an example of treatment process factors, Māori have been reported as being more likely than other groups to experience a delay of 8 weeks or more before starting chemotherapy.[[15]] We did not investigate treatment delay, but this is an important measure for future research in the management of lung cancer.
Aotearoa New Zealand has lagged behind other OECD nations with respect to subsidised access to immunotherapy treatments. The Aotearoa New Zealand drug-buying agency has only recently announced a decision to fund pembrolizumab and atezolizumab for the treatment of lung cancer.[[20]] Real-world data indicate that this is likely to improve median survival, especially for younger patients, by up to 5 months.[[21]] In Aotearoa New Zealand this long overdue announcement will lead to improved survival of lung cancer patients in general. It remains to be seen if this will also help close the survival gap between Māori and non-Māori.
A strength of this research is that our SACT database contains 20 years of complete and continuous data regarding individuals with lung cancer including age, gender, ethnicity, cancer stage, SACT regimens and date of death. As a limitation, our SACT dataset does not provide data on other risk factors including smoking status, comorbidities or socio-economic status, which may influence the pattern of cares and survival outcomes of advanced NSCLC patients.
Conclusion
Fifty-three percent of patients seen in our regional oncology centre with advanced NSCLC were treated with SACT. Patients that receive SACT have greater 1-year survival than those that do not. While the proportion of Māori commencing first-line treatment was the same as for non-Māori, there was less uptake of second-line treatment for Māori over non-Māori. Survival for Māori was consistently inferior to that of non-Māori.
Summary
Abstract
Aim
To investigate the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC) over a 20-year period in a single Aotearoa New Zealand centre with reference to the use of systemic anti-cancer chemotherapy (SACT) and to explore ethnic disparities in treatment and outcomes.
Method
Using a SACT database maintained by the Oncology Department at Waikato Hospital, Hamilton, Aotearoa New Zealand from 2000 to 2021 we derived summary statistics for patient factors and SACT regimens by ethnicity (Māori and non-Māori). We investigated Kaplan–Meier all-cause survival by ethnicity and SACT. Logistic regression was used to estimate the odds ratios of surviving 12 months and receiving first and second SACT.
Results
One thousand and fifty-seven patients with advanced NSCLC were included, with 30% identified as Māori and 53% treated with SACT. The median survival for non-Māori and Māori receiving SACT was 11.9 and 8.5 months respectively (unadjusted odds ratio of surviving 12 months: 1.968; 95% CI: 1.352–2.865; p<0.001). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori. There were no ethnic disparities in the proportion of patients receiving first-line SACT; however, non-Māori were 1.5 times more likely to receive a second SACT than Māori.
Conclusion
Significant ethnic difference between Māori and non-Māori exists for both survival and receipt of second-line SACT.
Author Information
Acknowledgements
Correspondence
Correspondence Email
Competing Interests
Te Whatu Ora – Health New Zealand. Cancer: Historical cancer data [Internet]. Ministry of Health; 2022 [cited 2023 May 29]. Available from: https://www.tewhatuora.govt.nz/our-health-system/data-and-statistics/historical-cancer/.
2. American Cancer Society. Lung Cancer Survival Rates [Internet]. 2022 [cited 2023 May 29]. Available from: https://www.cancer.org/cancer/lung-cancer/detection-diagnosis-staging/survival-rates.html.
3. Gurney J, Stanley J, McLeod M, et al. Disparities in Cancer-Specific Survival Between Māori and non-Māori New Zealanders, 2007-2016. JCO Glob Oncology. 2020;6:766-74. doi: 10.1200/GO.20.00028.
4. Arnold M, Rutherford MJ, Bardot A, et al. Progress in cancer survival, mortality, and incidence in seven high-income countries 1995–2014 (ICBP SURVMARK-2): a population-based study. Lancet Oncol. 2019;20(11):1493-1505. doi: 10.1016/S1470-2045(19)30456-5.
5. Lawrenson R, Seneviratne S, Scott N, et al. Breast cancer inequities between Māori and non‐Māori women in Aotearoa/New Zealand. Eur J Cancer Care (Engl). 2016;25(2):225-30. doi: 10.1111/ecc.12473.
6. Lao C, Kuper-Hommel M, Laking G, et al. Evidence of inequitable use of chemotherapy in New Zealand colorectal cancer patients. N Z Med J. 2020;133(1520):15-26.
7. Te Aho o Te Kahu. Lung Cancer Quality Improvement Monitoring Report 2021. Wellington, New Zealand: Cancer Control Agency; 2021 [cited 2023 May 29]. Available from: https://teaho.govt.nz/static/reports/lung-cancer-quality-improvement-monitoring-report-20210225.pdf.
8. Seneviratne S, Campbell I, Scott N, et al. Treatment delay for Māori women with breast cancer in New Zealand. Ethn Health. 2015;20(2):178-93. doi: 10.1080/13557858.2014.895976.
9. Riddell T, Jackson RT, Wells S, et al. Assessing Māori/non-Māori differences in cardiovascular disease risk and risk management in routine primary care practice using web-based clinical decision support: (PREDICT CVD-2). N Z Med J. 2007;120(1250):U2445.
10. Westbrooke I, Baxter J, Hogan J. Are Maori under-served for cardiac interventions? N Z Med J. 2001;114(1143):484-7.
11. Hofmarcher T, Lindgren P, Wilking N. Systemic anti-cancer therapy patterns in advanced non-small cell lung cancer in Europe. J Cancer Policy. 2022;34:100362. doi: 10.1016/j.jcpo.2022.100362.
12. Soares M, Antunes L, Redondo P, et al. Real-world treatment patterns and survival outcomes for advanced non-small cell lung cancer in the pre-immunotherapy era in Portugal: a retrospective analysis from the IO Optimise initiative. BMC Pulm Med. 2020;20(1):240. doi: 10.1186/s12890-020-01270-z.
13. Shepherd FA, Dancey J, Ramlau R, et al. Prospective randomized trial of docetaxel versus best supportive care in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy. J Clin Oncol. 2000;18(10):2095-2103. doi: 10.1200/JCO.2000.18.10.2095.
14. Crengle S, Lay-Yee R, Davis P, Pearson J. A Comparison of Māori and Non-Māori Patient Visits to Doctors: The National Primary Medical Care Survey (NatMedCa): 2001/02, Report 6. Wellington, New Zealand: Ministry of Health; 2005 [cited 2023 May 29]. Available from: https://www.moh.govt.nz/notebook/nbbooks.nsf/0/d222772d6d01d0facc25748c007d64d8/$FILE/NatMedCaReport6Dec2005.pdf.
15. Hill S, Sarfati D, Blakely T, et al. Survival disparities in Indigenous and non-Indigenous New Zealanders with colon cancer: the role of patient comorbidity, treatment and health service factors. J Epidemiol Community Health. 2010;64(2):117-23. doi: 10.1136/jech.2008.083816.
16. Shavers VL, Brown ML. Racial and ethnic disparities in the receipt of cancer treatment. J Natl Cancer Inst. 2002;94(5):334-57. doi: 10.1093/jnci/94.5.334.
17. Hill S, Sarfati D, Robson B, Blakely T. Indigenous inequalities in cancer: what role for health care? ANZ J Surg. 2013;83(1-2):36-41. doi: 10.1111/ans.12041.
18. Lawrenson R, Cassim S, Kidd J, et al. Ha ora: Improving access to early diagnosis of lung cancer for Maori and rural communities. Understanding patient experiences in General Practice (Report). Hamilton, New Zealand: University of Waikato; 2021.
19. Stevens W, Stevens G, Kolbe J, Cox B. Ethnic differences in the management of lung cancer in New Zealand. J Thorac Oncol. 2008;3(3):237-44. doi: 10.1097/JTO.0b013e3181653d08.
20. Pharmac. Decision to fund two new treatments for people with advanced non-small cell lung cancer [Internet]. 2023 [cited 2023 May 29]. Available from: https://pharmac.govt.nz/news-and-resources/consultations-and-decisions/2023-03-07-decision-to-fund-two-new-treatments-for-people-with-advanced-non-small-cell-lung-cancer/.
21. Voruganti T, Soulos PR, Mamtani R, et al. Association Between Age and Survival Trends in Advanced Non–Small Cell Lung Cancer After Adoption of Immunotherapy. JAMA Oncol. 2023;9(3):334-41. doi: 10.1001/jamaoncol.2022.6901.
For the PDF of this article,
contact nzmj@nzma.org.nz
Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study
View Article PDF
Lung cancer is the commonest cause of cancer death in Aotearoa New Zealand.[[1]] Most patients with non-small cell lung cancer (NSCLC) will have advanced disease at diagnosis. The prognosis for these patients is poor with an estimated historical 5-year survival of less than 10%.[[2,3]] Indeed, the 5-year overall survival for lung cancer across all stages in Aotearoa New Zealand in 2014 was only 15.5%, with just a 4% improvement from 1999.[[4]] Of particular concern has been the finding that Māori, the Indigenous people of Aotearoa New Zealand , have a 30% greater mortality from lung cancer compared to non-Māori.[[3]] Previous research has revealed ethnic disparity in cancer treatment—for instance, Māori with breast cancer are less likely to receive radiotherapy or long-term adjuvant endocrine therapy,[[5]] and Māori with colorectal cancer are less likely to receive chemotherapy.[[6–10]] There is scant research into ethnic differences in NSCLC treatment and its impacts on survival outcomes in Aotearoa New Zealand patients; hence, we sought to investigate possible differences in the use of systemic anti-cancer chemotherapy (SACT) in Māori and non-Māori.
Methods
Data source
This is a retrospective study based on a comprehensive dataset collected prospectively using a purpose-built SACT prescribing and database system from 1 January 2000 to 31 December 2021. We obtained patient-level data for individuals with a first diagnosis of advanced NSCLC referred to the Medical Oncology Unit Waikato Hospital. Waikato Hospital is the regional cancer centre for the central region of the North Island of Aotearoa New Zealand and provides care for approximately 800,000 people, of whom 30% identify as Māori. We collected information on the following variables: age, gender, ethnicity (Māori or non-Māori), date/year of lung cancer diagnosis, stage at diagnosis, SACT regimens prescribed and survival. We included only those patients with Stage 3 and 4 NSCLC. We excluded patients enrolled in clinical trials (22) and patients with epidermal growth factor receptor (EGFR) mutated lung cancer (95).
Analysis
We reviewed the characteristics and SACT regimens of lung cancer patients with advanced NSCLC. We investigated ethnic differences in patient factors and SACT regimens in those receiving first and second SACT regimens, and those not receiving SACT. We used Chi-squared tests to compare categorical variables and Student’s t-Tests for continuous variables.
Using the Kaplan–Meier method, we calculated all-cause survival after diagnosis of lung cancer for patients with and without SACT by ethnicity. We also analysed the all-cause survival in those receiving different SACT regimens (carboplatin plus pemetrexed, carboplatin plus gemcitabine, cisplatin plus gemcitabine, carboplatin plus paclitaxel, and other regimens) as their first-line treatments. Using logistic regression models, we examined the odds ratios (OR) of surviving 12 months in the entire cohort, adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. Then, we estimated the OR of surviving 12 months in the group receiving their first SACT regimen adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. OR of receiving first-line SACT or moving from first- to second-line SACT were also calculated, adjusting for age, gender, ethnicity and year of diagnosis. All analyses were carried out using Stata 15 (StataCorp LLC, Texas, United States).
Results
After excluding trial patients (22) and those with EGFR-mutated lung cancer (95), we identified 1,057 cases who had been referred to oncology with advanced-stage NSCLC. Table 1 shows that 562 (53%) were treated with SACT. The key factor associated with the likelihood of receiving SACT was the patient’s age, with older patients being less likely to be treated. Of those with NSCLC, 316/1,057 (30%) had been identified as Māori and there was no difference in the proportion of Māori and non-Māori who received SACT. Māori who received SACT were on average 1 year younger than non-Māori (mean age 62 years compared to 63 years in non-Māori, p=0.04). Non-Māori who did not receive SACT were older than Māori who did not receive SACT (mean 68 vs 61 years, p<0.01). The proportion of referred patients receiving treatment increased from 49% (65/133) in 2000–2004 to 55% (222/401) in 2015–2021 (Table 1). There was also an increase in the proportion receiving a second or subsequent SACT regimen from 11% (15/133) to 16% (64/401).
Table 2 shows the frequency of various regimens used as SACT. Of these, carboplatin plus gemcitabine and carboplatin plus paclitaxel were the most common, accounting for over half the chosen first-line regimens. A total of 166/562 (30%) patients received a second-line SACT regimen. Vinorelbine (51/166, 31%) and docetaxel (38/166, 23%) were the commonest second-line choices.
Of those treated with SACT, median survival for non-Māori was 11.9 months and for Māori 8.5 months. Overall median survival in those not treated was 4.7 months (Table 1). Kaplan–Meier survival analysis (Figure 1) showed that patients with advanced NSCLC had a poor prognosis with a 5-year survival of less than 10%. Outcomes were poorer for Māori in both those treated with and without SACT. Patients not receiving SACT had a 1-year survival of approximately 20%, while patients treated with SACT had a 1-year survival of approximately 40%. After 3 years, there was no difference in survival between those with and without SACT.
View Tables 1–4, Figure 1.
Table 3A demonstrates that patients treated with first-line SACT regimens were 2–3 times significantly more likely to survive 12 months than those not receiving SACT regimens (p<0.001) after adjustment for age, gender, ethnicity and year of diagnosis. As expected, there was no significant difference in survival between different first-line SACT regimens in those receiving SACT (Table 3B). For the entire cohort, non-Māori were 68.8% more likely to survive 12 months than Māori (Table 3A). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori (Table 3B). There was no ethnic difference in the proportion of patients receiving first-line SACT (adjusted OR: 1.096; 95% confidence interval [CI]: 0.833–1.443; p>0.05); however, non-Māori were significantly more likely than Māori to change from a first to a second SACT (adjusted OR: 1.536; 95% CI: 1.015–2.325; p<0.05, Table 4).
Discussion
Our study provides valuable insights into the treatment and survival outcomes of patients with advanced NSCLC based on an Aotearoa New Zealand SACT dataset derived over 20 years. Of patients with advanced NSCLC, 53% received first-line SACT, and 30% had second-line treatment. This proportion of advanced NSCLC patients treated with SACT is higher than in the United Kingdom (40%) but less than that in in Belgium, Norway and Portugal (75%).[[11]] Patients receiving SACT had better survival than those that did not. Median survival of patients treated with first SACT, second SACT and without SACT was 10.7, 17.5 and 4.7 months, respectively. A retrospective study of patients with advanced NSCLC in Portugal showed that patients not receiving SACT had a median survival of 1.8–2.3 months while those treated had a median survival of 10.3–12.6 months.[[12]]
The proportion of Māori and non-Māori patients treated with SACT were 54% and 53% respectively. We found no ethnic difference in receiving first-line SACT treatment. Randomised studies show a modest but statistically significant survival advantage of approximately 2 months for receipt of second-line chemotherapy compared to best supportive care.[[13]] It is therefore noteworthy that we found Māori patients with advanced NSCLC were less likely to receive second-line SACT. In addition, Māori receiving SACT were also less likely to survive 12 months than non-Māori. The reasons underlying ethnic disparities in cancer treatment and outcomes are complex. Social deprivation has a resultant influence on income, employment, housing and access to care, which are known key determinants of health. Over 60% of Māori patients live in localities that fall within the three most deprived deciles of the NZDep2001 Index of Deprivation.[[14]] Additionally, patient-level factors, treatment process factors and health system factors play a part.[[15–18]] As an example of patient-level factors, Māori are more likely to have comorbidities than non-Māori.[[17]] It has been reported that compared to non-Māori, Māori have a greater tendency to decline treatment,[[19]] but our study did not show a difference in uptake of first-line SACT. This may, however, be a factor in the lower transition to second-line SACT. As an example of treatment process factors, Māori have been reported as being more likely than other groups to experience a delay of 8 weeks or more before starting chemotherapy.[[15]] We did not investigate treatment delay, but this is an important measure for future research in the management of lung cancer.
Aotearoa New Zealand has lagged behind other OECD nations with respect to subsidised access to immunotherapy treatments. The Aotearoa New Zealand drug-buying agency has only recently announced a decision to fund pembrolizumab and atezolizumab for the treatment of lung cancer.[[20]] Real-world data indicate that this is likely to improve median survival, especially for younger patients, by up to 5 months.[[21]] In Aotearoa New Zealand this long overdue announcement will lead to improved survival of lung cancer patients in general. It remains to be seen if this will also help close the survival gap between Māori and non-Māori.
A strength of this research is that our SACT database contains 20 years of complete and continuous data regarding individuals with lung cancer including age, gender, ethnicity, cancer stage, SACT regimens and date of death. As a limitation, our SACT dataset does not provide data on other risk factors including smoking status, comorbidities or socio-economic status, which may influence the pattern of cares and survival outcomes of advanced NSCLC patients.
Conclusion
Fifty-three percent of patients seen in our regional oncology centre with advanced NSCLC were treated with SACT. Patients that receive SACT have greater 1-year survival than those that do not. While the proportion of Māori commencing first-line treatment was the same as for non-Māori, there was less uptake of second-line treatment for Māori over non-Māori. Survival for Māori was consistently inferior to that of non-Māori.
Summary
Abstract
Aim
To investigate the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC) over a 20-year period in a single Aotearoa New Zealand centre with reference to the use of systemic anti-cancer chemotherapy (SACT) and to explore ethnic disparities in treatment and outcomes.
Method
Using a SACT database maintained by the Oncology Department at Waikato Hospital, Hamilton, Aotearoa New Zealand from 2000 to 2021 we derived summary statistics for patient factors and SACT regimens by ethnicity (Māori and non-Māori). We investigated Kaplan–Meier all-cause survival by ethnicity and SACT. Logistic regression was used to estimate the odds ratios of surviving 12 months and receiving first and second SACT.
Results
One thousand and fifty-seven patients with advanced NSCLC were included, with 30% identified as Māori and 53% treated with SACT. The median survival for non-Māori and Māori receiving SACT was 11.9 and 8.5 months respectively (unadjusted odds ratio of surviving 12 months: 1.968; 95% CI: 1.352–2.865; p<0.001). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori. There were no ethnic disparities in the proportion of patients receiving first-line SACT; however, non-Māori were 1.5 times more likely to receive a second SACT than Māori.
Conclusion
Significant ethnic difference between Māori and non-Māori exists for both survival and receipt of second-line SACT.
Author Information
Acknowledgements
Correspondence
Correspondence Email
Competing Interests
Te Whatu Ora – Health New Zealand. Cancer: Historical cancer data [Internet]. Ministry of Health; 2022 [cited 2023 May 29]. Available from: https://www.tewhatuora.govt.nz/our-health-system/data-and-statistics/historical-cancer/.
2. American Cancer Society. Lung Cancer Survival Rates [Internet]. 2022 [cited 2023 May 29]. Available from: https://www.cancer.org/cancer/lung-cancer/detection-diagnosis-staging/survival-rates.html.
3. Gurney J, Stanley J, McLeod M, et al. Disparities in Cancer-Specific Survival Between Māori and non-Māori New Zealanders, 2007-2016. JCO Glob Oncology. 2020;6:766-74. doi: 10.1200/GO.20.00028.
4. Arnold M, Rutherford MJ, Bardot A, et al. Progress in cancer survival, mortality, and incidence in seven high-income countries 1995–2014 (ICBP SURVMARK-2): a population-based study. Lancet Oncol. 2019;20(11):1493-1505. doi: 10.1016/S1470-2045(19)30456-5.
5. Lawrenson R, Seneviratne S, Scott N, et al. Breast cancer inequities between Māori and non‐Māori women in Aotearoa/New Zealand. Eur J Cancer Care (Engl). 2016;25(2):225-30. doi: 10.1111/ecc.12473.
6. Lao C, Kuper-Hommel M, Laking G, et al. Evidence of inequitable use of chemotherapy in New Zealand colorectal cancer patients. N Z Med J. 2020;133(1520):15-26.
7. Te Aho o Te Kahu. Lung Cancer Quality Improvement Monitoring Report 2021. Wellington, New Zealand: Cancer Control Agency; 2021 [cited 2023 May 29]. Available from: https://teaho.govt.nz/static/reports/lung-cancer-quality-improvement-monitoring-report-20210225.pdf.
8. Seneviratne S, Campbell I, Scott N, et al. Treatment delay for Māori women with breast cancer in New Zealand. Ethn Health. 2015;20(2):178-93. doi: 10.1080/13557858.2014.895976.
9. Riddell T, Jackson RT, Wells S, et al. Assessing Māori/non-Māori differences in cardiovascular disease risk and risk management in routine primary care practice using web-based clinical decision support: (PREDICT CVD-2). N Z Med J. 2007;120(1250):U2445.
10. Westbrooke I, Baxter J, Hogan J. Are Maori under-served for cardiac interventions? N Z Med J. 2001;114(1143):484-7.
11. Hofmarcher T, Lindgren P, Wilking N. Systemic anti-cancer therapy patterns in advanced non-small cell lung cancer in Europe. J Cancer Policy. 2022;34:100362. doi: 10.1016/j.jcpo.2022.100362.
12. Soares M, Antunes L, Redondo P, et al. Real-world treatment patterns and survival outcomes for advanced non-small cell lung cancer in the pre-immunotherapy era in Portugal: a retrospective analysis from the IO Optimise initiative. BMC Pulm Med. 2020;20(1):240. doi: 10.1186/s12890-020-01270-z.
13. Shepherd FA, Dancey J, Ramlau R, et al. Prospective randomized trial of docetaxel versus best supportive care in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy. J Clin Oncol. 2000;18(10):2095-2103. doi: 10.1200/JCO.2000.18.10.2095.
14. Crengle S, Lay-Yee R, Davis P, Pearson J. A Comparison of Māori and Non-Māori Patient Visits to Doctors: The National Primary Medical Care Survey (NatMedCa): 2001/02, Report 6. Wellington, New Zealand: Ministry of Health; 2005 [cited 2023 May 29]. Available from: https://www.moh.govt.nz/notebook/nbbooks.nsf/0/d222772d6d01d0facc25748c007d64d8/$FILE/NatMedCaReport6Dec2005.pdf.
15. Hill S, Sarfati D, Blakely T, et al. Survival disparities in Indigenous and non-Indigenous New Zealanders with colon cancer: the role of patient comorbidity, treatment and health service factors. J Epidemiol Community Health. 2010;64(2):117-23. doi: 10.1136/jech.2008.083816.
16. Shavers VL, Brown ML. Racial and ethnic disparities in the receipt of cancer treatment. J Natl Cancer Inst. 2002;94(5):334-57. doi: 10.1093/jnci/94.5.334.
17. Hill S, Sarfati D, Robson B, Blakely T. Indigenous inequalities in cancer: what role for health care? ANZ J Surg. 2013;83(1-2):36-41. doi: 10.1111/ans.12041.
18. Lawrenson R, Cassim S, Kidd J, et al. Ha ora: Improving access to early diagnosis of lung cancer for Maori and rural communities. Understanding patient experiences in General Practice (Report). Hamilton, New Zealand: University of Waikato; 2021.
19. Stevens W, Stevens G, Kolbe J, Cox B. Ethnic differences in the management of lung cancer in New Zealand. J Thorac Oncol. 2008;3(3):237-44. doi: 10.1097/JTO.0b013e3181653d08.
20. Pharmac. Decision to fund two new treatments for people with advanced non-small cell lung cancer [Internet]. 2023 [cited 2023 May 29]. Available from: https://pharmac.govt.nz/news-and-resources/consultations-and-decisions/2023-03-07-decision-to-fund-two-new-treatments-for-people-with-advanced-non-small-cell-lung-cancer/.
21. Voruganti T, Soulos PR, Mamtani R, et al. Association Between Age and Survival Trends in Advanced Non–Small Cell Lung Cancer After Adoption of Immunotherapy. JAMA Oncol. 2023;9(3):334-41. doi: 10.1001/jamaoncol.2022.6901.
For the PDF of this article,
contact nzmj@nzma.org.nz
Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study
View Article PDF
Lung cancer is the commonest cause of cancer death in Aotearoa New Zealand.[[1]] Most patients with non-small cell lung cancer (NSCLC) will have advanced disease at diagnosis. The prognosis for these patients is poor with an estimated historical 5-year survival of less than 10%.[[2,3]] Indeed, the 5-year overall survival for lung cancer across all stages in Aotearoa New Zealand in 2014 was only 15.5%, with just a 4% improvement from 1999.[[4]] Of particular concern has been the finding that Māori, the Indigenous people of Aotearoa New Zealand , have a 30% greater mortality from lung cancer compared to non-Māori.[[3]] Previous research has revealed ethnic disparity in cancer treatment—for instance, Māori with breast cancer are less likely to receive radiotherapy or long-term adjuvant endocrine therapy,[[5]] and Māori with colorectal cancer are less likely to receive chemotherapy.[[6–10]] There is scant research into ethnic differences in NSCLC treatment and its impacts on survival outcomes in Aotearoa New Zealand patients; hence, we sought to investigate possible differences in the use of systemic anti-cancer chemotherapy (SACT) in Māori and non-Māori.
Methods
Data source
This is a retrospective study based on a comprehensive dataset collected prospectively using a purpose-built SACT prescribing and database system from 1 January 2000 to 31 December 2021. We obtained patient-level data for individuals with a first diagnosis of advanced NSCLC referred to the Medical Oncology Unit Waikato Hospital. Waikato Hospital is the regional cancer centre for the central region of the North Island of Aotearoa New Zealand and provides care for approximately 800,000 people, of whom 30% identify as Māori. We collected information on the following variables: age, gender, ethnicity (Māori or non-Māori), date/year of lung cancer diagnosis, stage at diagnosis, SACT regimens prescribed and survival. We included only those patients with Stage 3 and 4 NSCLC. We excluded patients enrolled in clinical trials (22) and patients with epidermal growth factor receptor (EGFR) mutated lung cancer (95).
Analysis
We reviewed the characteristics and SACT regimens of lung cancer patients with advanced NSCLC. We investigated ethnic differences in patient factors and SACT regimens in those receiving first and second SACT regimens, and those not receiving SACT. We used Chi-squared tests to compare categorical variables and Student’s t-Tests for continuous variables.
Using the Kaplan–Meier method, we calculated all-cause survival after diagnosis of lung cancer for patients with and without SACT by ethnicity. We also analysed the all-cause survival in those receiving different SACT regimens (carboplatin plus pemetrexed, carboplatin plus gemcitabine, cisplatin plus gemcitabine, carboplatin plus paclitaxel, and other regimens) as their first-line treatments. Using logistic regression models, we examined the odds ratios (OR) of surviving 12 months in the entire cohort, adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. Then, we estimated the OR of surviving 12 months in the group receiving their first SACT regimen adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. OR of receiving first-line SACT or moving from first- to second-line SACT were also calculated, adjusting for age, gender, ethnicity and year of diagnosis. All analyses were carried out using Stata 15 (StataCorp LLC, Texas, United States).
Results
After excluding trial patients (22) and those with EGFR-mutated lung cancer (95), we identified 1,057 cases who had been referred to oncology with advanced-stage NSCLC. Table 1 shows that 562 (53%) were treated with SACT. The key factor associated with the likelihood of receiving SACT was the patient’s age, with older patients being less likely to be treated. Of those with NSCLC, 316/1,057 (30%) had been identified as Māori and there was no difference in the proportion of Māori and non-Māori who received SACT. Māori who received SACT were on average 1 year younger than non-Māori (mean age 62 years compared to 63 years in non-Māori, p=0.04). Non-Māori who did not receive SACT were older than Māori who did not receive SACT (mean 68 vs 61 years, p<0.01). The proportion of referred patients receiving treatment increased from 49% (65/133) in 2000–2004 to 55% (222/401) in 2015–2021 (Table 1). There was also an increase in the proportion receiving a second or subsequent SACT regimen from 11% (15/133) to 16% (64/401).
Table 2 shows the frequency of various regimens used as SACT. Of these, carboplatin plus gemcitabine and carboplatin plus paclitaxel were the most common, accounting for over half the chosen first-line regimens. A total of 166/562 (30%) patients received a second-line SACT regimen. Vinorelbine (51/166, 31%) and docetaxel (38/166, 23%) were the commonest second-line choices.
Of those treated with SACT, median survival for non-Māori was 11.9 months and for Māori 8.5 months. Overall median survival in those not treated was 4.7 months (Table 1). Kaplan–Meier survival analysis (Figure 1) showed that patients with advanced NSCLC had a poor prognosis with a 5-year survival of less than 10%. Outcomes were poorer for Māori in both those treated with and without SACT. Patients not receiving SACT had a 1-year survival of approximately 20%, while patients treated with SACT had a 1-year survival of approximately 40%. After 3 years, there was no difference in survival between those with and without SACT.
View Tables 1–4, Figure 1.
Table 3A demonstrates that patients treated with first-line SACT regimens were 2–3 times significantly more likely to survive 12 months than those not receiving SACT regimens (p<0.001) after adjustment for age, gender, ethnicity and year of diagnosis. As expected, there was no significant difference in survival between different first-line SACT regimens in those receiving SACT (Table 3B). For the entire cohort, non-Māori were 68.8% more likely to survive 12 months than Māori (Table 3A). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori (Table 3B). There was no ethnic difference in the proportion of patients receiving first-line SACT (adjusted OR: 1.096; 95% confidence interval [CI]: 0.833–1.443; p>0.05); however, non-Māori were significantly more likely than Māori to change from a first to a second SACT (adjusted OR: 1.536; 95% CI: 1.015–2.325; p<0.05, Table 4).
Discussion
Our study provides valuable insights into the treatment and survival outcomes of patients with advanced NSCLC based on an Aotearoa New Zealand SACT dataset derived over 20 years. Of patients with advanced NSCLC, 53% received first-line SACT, and 30% had second-line treatment. This proportion of advanced NSCLC patients treated with SACT is higher than in the United Kingdom (40%) but less than that in in Belgium, Norway and Portugal (75%).[[11]] Patients receiving SACT had better survival than those that did not. Median survival of patients treated with first SACT, second SACT and without SACT was 10.7, 17.5 and 4.7 months, respectively. A retrospective study of patients with advanced NSCLC in Portugal showed that patients not receiving SACT had a median survival of 1.8–2.3 months while those treated had a median survival of 10.3–12.6 months.[[12]]
The proportion of Māori and non-Māori patients treated with SACT were 54% and 53% respectively. We found no ethnic difference in receiving first-line SACT treatment. Randomised studies show a modest but statistically significant survival advantage of approximately 2 months for receipt of second-line chemotherapy compared to best supportive care.[[13]] It is therefore noteworthy that we found Māori patients with advanced NSCLC were less likely to receive second-line SACT. In addition, Māori receiving SACT were also less likely to survive 12 months than non-Māori. The reasons underlying ethnic disparities in cancer treatment and outcomes are complex. Social deprivation has a resultant influence on income, employment, housing and access to care, which are known key determinants of health. Over 60% of Māori patients live in localities that fall within the three most deprived deciles of the NZDep2001 Index of Deprivation.[[14]] Additionally, patient-level factors, treatment process factors and health system factors play a part.[[15–18]] As an example of patient-level factors, Māori are more likely to have comorbidities than non-Māori.[[17]] It has been reported that compared to non-Māori, Māori have a greater tendency to decline treatment,[[19]] but our study did not show a difference in uptake of first-line SACT. This may, however, be a factor in the lower transition to second-line SACT. As an example of treatment process factors, Māori have been reported as being more likely than other groups to experience a delay of 8 weeks or more before starting chemotherapy.[[15]] We did not investigate treatment delay, but this is an important measure for future research in the management of lung cancer.
Aotearoa New Zealand has lagged behind other OECD nations with respect to subsidised access to immunotherapy treatments. The Aotearoa New Zealand drug-buying agency has only recently announced a decision to fund pembrolizumab and atezolizumab for the treatment of lung cancer.[[20]] Real-world data indicate that this is likely to improve median survival, especially for younger patients, by up to 5 months.[[21]] In Aotearoa New Zealand this long overdue announcement will lead to improved survival of lung cancer patients in general. It remains to be seen if this will also help close the survival gap between Māori and non-Māori.
A strength of this research is that our SACT database contains 20 years of complete and continuous data regarding individuals with lung cancer including age, gender, ethnicity, cancer stage, SACT regimens and date of death. As a limitation, our SACT dataset does not provide data on other risk factors including smoking status, comorbidities or socio-economic status, which may influence the pattern of cares and survival outcomes of advanced NSCLC patients.
Conclusion
Fifty-three percent of patients seen in our regional oncology centre with advanced NSCLC were treated with SACT. Patients that receive SACT have greater 1-year survival than those that do not. While the proportion of Māori commencing first-line treatment was the same as for non-Māori, there was less uptake of second-line treatment for Māori over non-Māori. Survival for Māori was consistently inferior to that of non-Māori.
Summary
Abstract
Aim
To investigate the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC) over a 20-year period in a single Aotearoa New Zealand centre with reference to the use of systemic anti-cancer chemotherapy (SACT) and to explore ethnic disparities in treatment and outcomes.
Method
Using a SACT database maintained by the Oncology Department at Waikato Hospital, Hamilton, Aotearoa New Zealand from 2000 to 2021 we derived summary statistics for patient factors and SACT regimens by ethnicity (Māori and non-Māori). We investigated Kaplan–Meier all-cause survival by ethnicity and SACT. Logistic regression was used to estimate the odds ratios of surviving 12 months and receiving first and second SACT.
Results
One thousand and fifty-seven patients with advanced NSCLC were included, with 30% identified as Māori and 53% treated with SACT. The median survival for non-Māori and Māori receiving SACT was 11.9 and 8.5 months respectively (unadjusted odds ratio of surviving 12 months: 1.968; 95% CI: 1.352–2.865; p<0.001). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori. There were no ethnic disparities in the proportion of patients receiving first-line SACT; however, non-Māori were 1.5 times more likely to receive a second SACT than Māori.
Conclusion
Significant ethnic difference between Māori and non-Māori exists for both survival and receipt of second-line SACT.
Author Information
Acknowledgements
Correspondence
Correspondence Email
Competing Interests
Te Whatu Ora – Health New Zealand. Cancer: Historical cancer data [Internet]. Ministry of Health; 2022 [cited 2023 May 29]. Available from: https://www.tewhatuora.govt.nz/our-health-system/data-and-statistics/historical-cancer/.
2. American Cancer Society. Lung Cancer Survival Rates [Internet]. 2022 [cited 2023 May 29]. Available from: https://www.cancer.org/cancer/lung-cancer/detection-diagnosis-staging/survival-rates.html.
3. Gurney J, Stanley J, McLeod M, et al. Disparities in Cancer-Specific Survival Between Māori and non-Māori New Zealanders, 2007-2016. JCO Glob Oncology. 2020;6:766-74. doi: 10.1200/GO.20.00028.
4. Arnold M, Rutherford MJ, Bardot A, et al. Progress in cancer survival, mortality, and incidence in seven high-income countries 1995–2014 (ICBP SURVMARK-2): a population-based study. Lancet Oncol. 2019;20(11):1493-1505. doi: 10.1016/S1470-2045(19)30456-5.
5. Lawrenson R, Seneviratne S, Scott N, et al. Breast cancer inequities between Māori and non‐Māori women in Aotearoa/New Zealand. Eur J Cancer Care (Engl). 2016;25(2):225-30. doi: 10.1111/ecc.12473.
6. Lao C, Kuper-Hommel M, Laking G, et al. Evidence of inequitable use of chemotherapy in New Zealand colorectal cancer patients. N Z Med J. 2020;133(1520):15-26.
7. Te Aho o Te Kahu. Lung Cancer Quality Improvement Monitoring Report 2021. Wellington, New Zealand: Cancer Control Agency; 2021 [cited 2023 May 29]. Available from: https://teaho.govt.nz/static/reports/lung-cancer-quality-improvement-monitoring-report-20210225.pdf.
8. Seneviratne S, Campbell I, Scott N, et al. Treatment delay for Māori women with breast cancer in New Zealand. Ethn Health. 2015;20(2):178-93. doi: 10.1080/13557858.2014.895976.
9. Riddell T, Jackson RT, Wells S, et al. Assessing Māori/non-Māori differences in cardiovascular disease risk and risk management in routine primary care practice using web-based clinical decision support: (PREDICT CVD-2). N Z Med J. 2007;120(1250):U2445.
10. Westbrooke I, Baxter J, Hogan J. Are Maori under-served for cardiac interventions? N Z Med J. 2001;114(1143):484-7.
11. Hofmarcher T, Lindgren P, Wilking N. Systemic anti-cancer therapy patterns in advanced non-small cell lung cancer in Europe. J Cancer Policy. 2022;34:100362. doi: 10.1016/j.jcpo.2022.100362.
12. Soares M, Antunes L, Redondo P, et al. Real-world treatment patterns and survival outcomes for advanced non-small cell lung cancer in the pre-immunotherapy era in Portugal: a retrospective analysis from the IO Optimise initiative. BMC Pulm Med. 2020;20(1):240. doi: 10.1186/s12890-020-01270-z.
13. Shepherd FA, Dancey J, Ramlau R, et al. Prospective randomized trial of docetaxel versus best supportive care in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy. J Clin Oncol. 2000;18(10):2095-2103. doi: 10.1200/JCO.2000.18.10.2095.
14. Crengle S, Lay-Yee R, Davis P, Pearson J. A Comparison of Māori and Non-Māori Patient Visits to Doctors: The National Primary Medical Care Survey (NatMedCa): 2001/02, Report 6. Wellington, New Zealand: Ministry of Health; 2005 [cited 2023 May 29]. Available from: https://www.moh.govt.nz/notebook/nbbooks.nsf/0/d222772d6d01d0facc25748c007d64d8/$FILE/NatMedCaReport6Dec2005.pdf.
15. Hill S, Sarfati D, Blakely T, et al. Survival disparities in Indigenous and non-Indigenous New Zealanders with colon cancer: the role of patient comorbidity, treatment and health service factors. J Epidemiol Community Health. 2010;64(2):117-23. doi: 10.1136/jech.2008.083816.
16. Shavers VL, Brown ML. Racial and ethnic disparities in the receipt of cancer treatment. J Natl Cancer Inst. 2002;94(5):334-57. doi: 10.1093/jnci/94.5.334.
17. Hill S, Sarfati D, Robson B, Blakely T. Indigenous inequalities in cancer: what role for health care? ANZ J Surg. 2013;83(1-2):36-41. doi: 10.1111/ans.12041.
18. Lawrenson R, Cassim S, Kidd J, et al. Ha ora: Improving access to early diagnosis of lung cancer for Maori and rural communities. Understanding patient experiences in General Practice (Report). Hamilton, New Zealand: University of Waikato; 2021.
19. Stevens W, Stevens G, Kolbe J, Cox B. Ethnic differences in the management of lung cancer in New Zealand. J Thorac Oncol. 2008;3(3):237-44. doi: 10.1097/JTO.0b013e3181653d08.
20. Pharmac. Decision to fund two new treatments for people with advanced non-small cell lung cancer [Internet]. 2023 [cited 2023 May 29]. Available from: https://pharmac.govt.nz/news-and-resources/consultations-and-decisions/2023-03-07-decision-to-fund-two-new-treatments-for-people-with-advanced-non-small-cell-lung-cancer/.
21. Voruganti T, Soulos PR, Mamtani R, et al. Association Between Age and Survival Trends in Advanced Non–Small Cell Lung Cancer After Adoption of Immunotherapy. JAMA Oncol. 2023;9(3):334-41. doi: 10.1001/jamaoncol.2022.6901.
Contact diana@nzma.org.nz
for the PDF of this article
Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study
View Article PDF
Lung cancer is the commonest cause of cancer death in Aotearoa New Zealand.[[1]] Most patients with non-small cell lung cancer (NSCLC) will have advanced disease at diagnosis. The prognosis for these patients is poor with an estimated historical 5-year survival of less than 10%.[[2,3]] Indeed, the 5-year overall survival for lung cancer across all stages in Aotearoa New Zealand in 2014 was only 15.5%, with just a 4% improvement from 1999.[[4]] Of particular concern has been the finding that Māori, the Indigenous people of Aotearoa New Zealand , have a 30% greater mortality from lung cancer compared to non-Māori.[[3]] Previous research has revealed ethnic disparity in cancer treatment—for instance, Māori with breast cancer are less likely to receive radiotherapy or long-term adjuvant endocrine therapy,[[5]] and Māori with colorectal cancer are less likely to receive chemotherapy.[[6–10]] There is scant research into ethnic differences in NSCLC treatment and its impacts on survival outcomes in Aotearoa New Zealand patients; hence, we sought to investigate possible differences in the use of systemic anti-cancer chemotherapy (SACT) in Māori and non-Māori.
Methods
Data source
This is a retrospective study based on a comprehensive dataset collected prospectively using a purpose-built SACT prescribing and database system from 1 January 2000 to 31 December 2021. We obtained patient-level data for individuals with a first diagnosis of advanced NSCLC referred to the Medical Oncology Unit Waikato Hospital. Waikato Hospital is the regional cancer centre for the central region of the North Island of Aotearoa New Zealand and provides care for approximately 800,000 people, of whom 30% identify as Māori. We collected information on the following variables: age, gender, ethnicity (Māori or non-Māori), date/year of lung cancer diagnosis, stage at diagnosis, SACT regimens prescribed and survival. We included only those patients with Stage 3 and 4 NSCLC. We excluded patients enrolled in clinical trials (22) and patients with epidermal growth factor receptor (EGFR) mutated lung cancer (95).
Analysis
We reviewed the characteristics and SACT regimens of lung cancer patients with advanced NSCLC. We investigated ethnic differences in patient factors and SACT regimens in those receiving first and second SACT regimens, and those not receiving SACT. We used Chi-squared tests to compare categorical variables and Student’s t-Tests for continuous variables.
Using the Kaplan–Meier method, we calculated all-cause survival after diagnosis of lung cancer for patients with and without SACT by ethnicity. We also analysed the all-cause survival in those receiving different SACT regimens (carboplatin plus pemetrexed, carboplatin plus gemcitabine, cisplatin plus gemcitabine, carboplatin plus paclitaxel, and other regimens) as their first-line treatments. Using logistic regression models, we examined the odds ratios (OR) of surviving 12 months in the entire cohort, adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. Then, we estimated the OR of surviving 12 months in the group receiving their first SACT regimen adjusting for age, gender, ethnicity, year of diagnosis and SACT regimens. OR of receiving first-line SACT or moving from first- to second-line SACT were also calculated, adjusting for age, gender, ethnicity and year of diagnosis. All analyses were carried out using Stata 15 (StataCorp LLC, Texas, United States).
Results
After excluding trial patients (22) and those with EGFR-mutated lung cancer (95), we identified 1,057 cases who had been referred to oncology with advanced-stage NSCLC. Table 1 shows that 562 (53%) were treated with SACT. The key factor associated with the likelihood of receiving SACT was the patient’s age, with older patients being less likely to be treated. Of those with NSCLC, 316/1,057 (30%) had been identified as Māori and there was no difference in the proportion of Māori and non-Māori who received SACT. Māori who received SACT were on average 1 year younger than non-Māori (mean age 62 years compared to 63 years in non-Māori, p=0.04). Non-Māori who did not receive SACT were older than Māori who did not receive SACT (mean 68 vs 61 years, p<0.01). The proportion of referred patients receiving treatment increased from 49% (65/133) in 2000–2004 to 55% (222/401) in 2015–2021 (Table 1). There was also an increase in the proportion receiving a second or subsequent SACT regimen from 11% (15/133) to 16% (64/401).
Table 2 shows the frequency of various regimens used as SACT. Of these, carboplatin plus gemcitabine and carboplatin plus paclitaxel were the most common, accounting for over half the chosen first-line regimens. A total of 166/562 (30%) patients received a second-line SACT regimen. Vinorelbine (51/166, 31%) and docetaxel (38/166, 23%) were the commonest second-line choices.
Of those treated with SACT, median survival for non-Māori was 11.9 months and for Māori 8.5 months. Overall median survival in those not treated was 4.7 months (Table 1). Kaplan–Meier survival analysis (Figure 1) showed that patients with advanced NSCLC had a poor prognosis with a 5-year survival of less than 10%. Outcomes were poorer for Māori in both those treated with and without SACT. Patients not receiving SACT had a 1-year survival of approximately 20%, while patients treated with SACT had a 1-year survival of approximately 40%. After 3 years, there was no difference in survival between those with and without SACT.
View Tables 1–4, Figure 1.
Table 3A demonstrates that patients treated with first-line SACT regimens were 2–3 times significantly more likely to survive 12 months than those not receiving SACT regimens (p<0.001) after adjustment for age, gender, ethnicity and year of diagnosis. As expected, there was no significant difference in survival between different first-line SACT regimens in those receiving SACT (Table 3B). For the entire cohort, non-Māori were 68.8% more likely to survive 12 months than Māori (Table 3A). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori (Table 3B). There was no ethnic difference in the proportion of patients receiving first-line SACT (adjusted OR: 1.096; 95% confidence interval [CI]: 0.833–1.443; p>0.05); however, non-Māori were significantly more likely than Māori to change from a first to a second SACT (adjusted OR: 1.536; 95% CI: 1.015–2.325; p<0.05, Table 4).
Discussion
Our study provides valuable insights into the treatment and survival outcomes of patients with advanced NSCLC based on an Aotearoa New Zealand SACT dataset derived over 20 years. Of patients with advanced NSCLC, 53% received first-line SACT, and 30% had second-line treatment. This proportion of advanced NSCLC patients treated with SACT is higher than in the United Kingdom (40%) but less than that in in Belgium, Norway and Portugal (75%).[[11]] Patients receiving SACT had better survival than those that did not. Median survival of patients treated with first SACT, second SACT and without SACT was 10.7, 17.5 and 4.7 months, respectively. A retrospective study of patients with advanced NSCLC in Portugal showed that patients not receiving SACT had a median survival of 1.8–2.3 months while those treated had a median survival of 10.3–12.6 months.[[12]]
The proportion of Māori and non-Māori patients treated with SACT were 54% and 53% respectively. We found no ethnic difference in receiving first-line SACT treatment. Randomised studies show a modest but statistically significant survival advantage of approximately 2 months for receipt of second-line chemotherapy compared to best supportive care.[[13]] It is therefore noteworthy that we found Māori patients with advanced NSCLC were less likely to receive second-line SACT. In addition, Māori receiving SACT were also less likely to survive 12 months than non-Māori. The reasons underlying ethnic disparities in cancer treatment and outcomes are complex. Social deprivation has a resultant influence on income, employment, housing and access to care, which are known key determinants of health. Over 60% of Māori patients live in localities that fall within the three most deprived deciles of the NZDep2001 Index of Deprivation.[[14]] Additionally, patient-level factors, treatment process factors and health system factors play a part.[[15–18]] As an example of patient-level factors, Māori are more likely to have comorbidities than non-Māori.[[17]] It has been reported that compared to non-Māori, Māori have a greater tendency to decline treatment,[[19]] but our study did not show a difference in uptake of first-line SACT. This may, however, be a factor in the lower transition to second-line SACT. As an example of treatment process factors, Māori have been reported as being more likely than other groups to experience a delay of 8 weeks or more before starting chemotherapy.[[15]] We did not investigate treatment delay, but this is an important measure for future research in the management of lung cancer.
Aotearoa New Zealand has lagged behind other OECD nations with respect to subsidised access to immunotherapy treatments. The Aotearoa New Zealand drug-buying agency has only recently announced a decision to fund pembrolizumab and atezolizumab for the treatment of lung cancer.[[20]] Real-world data indicate that this is likely to improve median survival, especially for younger patients, by up to 5 months.[[21]] In Aotearoa New Zealand this long overdue announcement will lead to improved survival of lung cancer patients in general. It remains to be seen if this will also help close the survival gap between Māori and non-Māori.
A strength of this research is that our SACT database contains 20 years of complete and continuous data regarding individuals with lung cancer including age, gender, ethnicity, cancer stage, SACT regimens and date of death. As a limitation, our SACT dataset does not provide data on other risk factors including smoking status, comorbidities or socio-economic status, which may influence the pattern of cares and survival outcomes of advanced NSCLC patients.
Conclusion
Fifty-three percent of patients seen in our regional oncology centre with advanced NSCLC were treated with SACT. Patients that receive SACT have greater 1-year survival than those that do not. While the proportion of Māori commencing first-line treatment was the same as for non-Māori, there was less uptake of second-line treatment for Māori over non-Māori. Survival for Māori was consistently inferior to that of non-Māori.
Summary
Abstract
Aim
To investigate the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC) over a 20-year period in a single Aotearoa New Zealand centre with reference to the use of systemic anti-cancer chemotherapy (SACT) and to explore ethnic disparities in treatment and outcomes.
Method
Using a SACT database maintained by the Oncology Department at Waikato Hospital, Hamilton, Aotearoa New Zealand from 2000 to 2021 we derived summary statistics for patient factors and SACT regimens by ethnicity (Māori and non-Māori). We investigated Kaplan–Meier all-cause survival by ethnicity and SACT. Logistic regression was used to estimate the odds ratios of surviving 12 months and receiving first and second SACT.
Results
One thousand and fifty-seven patients with advanced NSCLC were included, with 30% identified as Māori and 53% treated with SACT. The median survival for non-Māori and Māori receiving SACT was 11.9 and 8.5 months respectively (unadjusted odds ratio of surviving 12 months: 1.968; 95% CI: 1.352–2.865; p<0.001). Non-Māori receiving SACT were 86.2% more likely to survive 12 months than Māori. There were no ethnic disparities in the proportion of patients receiving first-line SACT; however, non-Māori were 1.5 times more likely to receive a second SACT than Māori.
Conclusion
Significant ethnic difference between Māori and non-Māori exists for both survival and receipt of second-line SACT.
Author Information
Acknowledgements
Correspondence
Correspondence Email
Competing Interests
Te Whatu Ora – Health New Zealand. Cancer: Historical cancer data [Internet]. Ministry of Health; 2022 [cited 2023 May 29]. Available from: https://www.tewhatuora.govt.nz/our-health-system/data-and-statistics/historical-cancer/.
2. American Cancer Society. Lung Cancer Survival Rates [Internet]. 2022 [cited 2023 May 29]. Available from: https://www.cancer.org/cancer/lung-cancer/detection-diagnosis-staging/survival-rates.html.
3. Gurney J, Stanley J, McLeod M, et al. Disparities in Cancer-Specific Survival Between Māori and non-Māori New Zealanders, 2007-2016. JCO Glob Oncology. 2020;6:766-74. doi: 10.1200/GO.20.00028.
4. Arnold M, Rutherford MJ, Bardot A, et al. Progress in cancer survival, mortality, and incidence in seven high-income countries 1995–2014 (ICBP SURVMARK-2): a population-based study. Lancet Oncol. 2019;20(11):1493-1505. doi: 10.1016/S1470-2045(19)30456-5.
5. Lawrenson R, Seneviratne S, Scott N, et al. Breast cancer inequities between Māori and non‐Māori women in Aotearoa/New Zealand. Eur J Cancer Care (Engl). 2016;25(2):225-30. doi: 10.1111/ecc.12473.
6. Lao C, Kuper-Hommel M, Laking G, et al. Evidence of inequitable use of chemotherapy in New Zealand colorectal cancer patients. N Z Med J. 2020;133(1520):15-26.
7. Te Aho o Te Kahu. Lung Cancer Quality Improvement Monitoring Report 2021. Wellington, New Zealand: Cancer Control Agency; 2021 [cited 2023 May 29]. Available from: https://teaho.govt.nz/static/reports/lung-cancer-quality-improvement-monitoring-report-20210225.pdf.
8. Seneviratne S, Campbell I, Scott N, et al. Treatment delay for Māori women with breast cancer in New Zealand. Ethn Health. 2015;20(2):178-93. doi: 10.1080/13557858.2014.895976.
9. Riddell T, Jackson RT, Wells S, et al. Assessing Māori/non-Māori differences in cardiovascular disease risk and risk management in routine primary care practice using web-based clinical decision support: (PREDICT CVD-2). N Z Med J. 2007;120(1250):U2445.
10. Westbrooke I, Baxter J, Hogan J. Are Maori under-served for cardiac interventions? N Z Med J. 2001;114(1143):484-7.
11. Hofmarcher T, Lindgren P, Wilking N. Systemic anti-cancer therapy patterns in advanced non-small cell lung cancer in Europe. J Cancer Policy. 2022;34:100362. doi: 10.1016/j.jcpo.2022.100362.
12. Soares M, Antunes L, Redondo P, et al. Real-world treatment patterns and survival outcomes for advanced non-small cell lung cancer in the pre-immunotherapy era in Portugal: a retrospective analysis from the IO Optimise initiative. BMC Pulm Med. 2020;20(1):240. doi: 10.1186/s12890-020-01270-z.
13. Shepherd FA, Dancey J, Ramlau R, et al. Prospective randomized trial of docetaxel versus best supportive care in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy. J Clin Oncol. 2000;18(10):2095-2103. doi: 10.1200/JCO.2000.18.10.2095.
14. Crengle S, Lay-Yee R, Davis P, Pearson J. A Comparison of Māori and Non-Māori Patient Visits to Doctors: The National Primary Medical Care Survey (NatMedCa): 2001/02, Report 6. Wellington, New Zealand: Ministry of Health; 2005 [cited 2023 May 29]. Available from: https://www.moh.govt.nz/notebook/nbbooks.nsf/0/d222772d6d01d0facc25748c007d64d8/$FILE/NatMedCaReport6Dec2005.pdf.
15. Hill S, Sarfati D, Blakely T, et al. Survival disparities in Indigenous and non-Indigenous New Zealanders with colon cancer: the role of patient comorbidity, treatment and health service factors. J Epidemiol Community Health. 2010;64(2):117-23. doi: 10.1136/jech.2008.083816.
16. Shavers VL, Brown ML. Racial and ethnic disparities in the receipt of cancer treatment. J Natl Cancer Inst. 2002;94(5):334-57. doi: 10.1093/jnci/94.5.334.
17. Hill S, Sarfati D, Robson B, Blakely T. Indigenous inequalities in cancer: what role for health care? ANZ J Surg. 2013;83(1-2):36-41. doi: 10.1111/ans.12041.
18. Lawrenson R, Cassim S, Kidd J, et al. Ha ora: Improving access to early diagnosis of lung cancer for Maori and rural communities. Understanding patient experiences in General Practice (Report). Hamilton, New Zealand: University of Waikato; 2021.
19. Stevens W, Stevens G, Kolbe J, Cox B. Ethnic differences in the management of lung cancer in New Zealand. J Thorac Oncol. 2008;3(3):237-44. doi: 10.1097/JTO.0b013e3181653d08.
20. Pharmac. Decision to fund two new treatments for people with advanced non-small cell lung cancer [Internet]. 2023 [cited 2023 May 29]. Available from: https://pharmac.govt.nz/news-and-resources/consultations-and-decisions/2023-03-07-decision-to-fund-two-new-treatments-for-people-with-advanced-non-small-cell-lung-cancer/.
21. Voruganti T, Soulos PR, Mamtani R, et al. Association Between Age and Survival Trends in Advanced Non–Small Cell Lung Cancer After Adoption of Immunotherapy. JAMA Oncol. 2023;9(3):334-41. doi: 10.1001/jamaoncol.2022.6901.
Contact diana@nzma.org.nz
for the PDF of this article
Non-small cell lung cancer chemotherapy treatment outcomes and ethnicity: a twenty-year single-centre patterns of care study
Lung cancer is the commonest cause of cancer death in Aotearoa New Zealand.
Subscriber Content
The full contents of this pages only available to subscribers.
Login, subscribe or email nzmj@nzma.org.nz to purchase this article.
