Clinical A 49-year-old lady presented with a 6-week history of a painless, enlarging lesion on her right eye. There were no visual symptoms nor any previous ocular surgery or trauma. Examination revealed a conjunctival mass measuring 4mm by 4.5mm by 3mm without any scleral attachment (Figures 1 and 2). The differential diagnosis included a foreign body-induced granuloma, pyogenic granuloma, conjunctival intraepithelial neoplasm, and an amelanotic melanoma. Figure 1. Amelanotic conjunctival melanoma (front view) Figure 2. Amelanotic conjunctival melanoma (side view) A wide local excision of the lesion with a conjunctival autograft was performed. Histological analysis revealed an amelanotic melanoma with clear surgical margins. A liver MRI scan did not show any metastasis. After consultation with a specialist ocular oncology centre, no immediate adjuvant therapy was planned. However, the patient remains under close follow-up to detect any tumour recurrence. Discussion Conjunctival melanomas have an annual incidence of 0.2-0.5 per million in Western populations.1 Although they are typically pigmented, amelanotic and minimally-pigmented conjunctival melanomas comprise up to 19% of cases.2 Notably, 9-25% of patients develop systemic metastasis and there is a significant mortality of 13-38% at 10 years.2 As illustrated by this case, amelanotic conjunctival melanomas can mimic benign lesions and should be considered in cases of non-pigmented, rapidly growing conjunctival lesions.

Clinical A 49-year-old lady presented with a 6-week history of a painless, enlarging lesion on her right eye. There were no visual symptoms nor any previous ocular surgery or trauma. Examination revealed a conjunctival mass measuring 4mm by 4.5mm by 3mm without any scleral attachment (Figures 1 and 2). The differential diagnosis included a foreign body-induced granuloma, pyogenic granuloma, conjunctival intraepithelial neoplasm, and an amelanotic melanoma. Figure 1. Amelanotic conjunctival melanoma (front view) Figure 2. Amelanotic conjunctival melanoma (side view) A wide local excision of the lesion with a conjunctival autograft was performed. Histological analysis revealed an amelanotic melanoma with clear surgical margins. A liver MRI scan did not show any metastasis. After consultation with a specialist ocular oncology centre, no immediate adjuvant therapy was planned. However, the patient remains under close follow-up to detect any tumour recurrence. Discussion Conjunctival melanomas have an annual incidence of 0.2-0.5 per million in Western populations.1 Although they are typically pigmented, amelanotic and minimally-pigmented conjunctival melanomas comprise up to 19% of cases.2 Notably, 9-25% of patients develop systemic metastasis and there is a significant mortality of 13-38% at 10 years.2 As illustrated by this case, amelanotic conjunctival melanomas can mimic benign lesions and should be considered in cases of non-pigmented, rapidly growing conjunctival lesions.