A fungating tumour (measuring 7.9x8.5x7.5cm) on a 71-year-old patients right buttock (Figure 1).Initial histopathological diagnosis was dermatofibrosarcoma protuberans (DFSP). Presenting as a small mass, it grew rapidly over 3 months. Repeat biopsy revealed high-grade spindle cell sarcoma. Clinically, the patient displayed ongoing systemic inflammatory response syndrome with coagulopathy and hyperdynamic circulation preventing surgical intervention. She had no pre-existing co-morbidities. Urgent palliative radiotherapy (Figure 2) achieved haemostasis at the bleeding tumour and subsequently the inflammatory response improved significantly.Two weeks post radiotherapy, the patient underwent palliative surgical resection of this large mass. Unfortunately, restaging scans showed progressive pulmonary metastases. She continues to receive follow-up with oncologists for monitoring and consideration of systemic agents.Dermatofibrosarcoma protuberans is a low-grade spindle cell neoplasm that constitutes 1% of all soft-tissue sarcomas,1 but it is the most common sarcoma of cutaneous origin with high cure rate.2 DFSP typically grows slowly over years with small rate of distant metastasis at 2-5%.1 Rarely, DFSP can transform into the more aggressive DFSP-fibrosarcomatous variant which is shown to have a higher local recurrence and metastatic potential.2The standard treatment is wide local excision with at least a 2 cm margin, however, when the tumour starts as a protruding mass, it has been shown to pose diagnostic and reconstructive challenges.3This case highlights that early referral to dermatologists and repeat biopsy of skin mass is crucial as we need to stay mindful of alternate diagnoses when the clinical picture is disparate with the natural history of the working diagnosis.Figure 1: Fungating tumour on right buttock Figure 2: Tumour during course of palliative radiotherapy

A fungating tumour (measuring 7.9x8.5x7.5cm) on a 71-year-old patients right buttock (Figure 1).Initial histopathological diagnosis was dermatofibrosarcoma protuberans (DFSP). Presenting as a small mass, it grew rapidly over 3 months. Repeat biopsy revealed high-grade spindle cell sarcoma. Clinically, the patient displayed ongoing systemic inflammatory response syndrome with coagulopathy and hyperdynamic circulation preventing surgical intervention. She had no pre-existing co-morbidities. Urgent palliative radiotherapy (Figure 2) achieved haemostasis at the bleeding tumour and subsequently the inflammatory response improved significantly.Two weeks post radiotherapy, the patient underwent palliative surgical resection of this large mass. Unfortunately, restaging scans showed progressive pulmonary metastases. She continues to receive follow-up with oncologists for monitoring and consideration of systemic agents.Dermatofibrosarcoma protuberans is a low-grade spindle cell neoplasm that constitutes 1% of all soft-tissue sarcomas,1 but it is the most common sarcoma of cutaneous origin with high cure rate.2 DFSP typically grows slowly over years with small rate of distant metastasis at 2-5%.1 Rarely, DFSP can transform into the more aggressive DFSP-fibrosarcomatous variant which is shown to have a higher local recurrence and metastatic potential.2The standard treatment is wide local excision with at least a 2 cm margin, however, when the tumour starts as a protruding mass, it has been shown to pose diagnostic and reconstructive challenges.3This case highlights that early referral to dermatologists and repeat biopsy of skin mass is crucial as we need to stay mindful of alternate diagnoses when the clinical picture is disparate with the natural history of the working diagnosis.Figure 1: Fungating tumour on right buttock Figure 2: Tumour during course of palliative radiotherapy