(BMJ)—A man in his 50s had a bleeding lesion behind his right ear for 4 months. No hx of trauma. Exam: 8-mm eroded, ulcerated, and bleeding nodule with hyperpigmented base. What’s the dx?
Keratoacanthoma
Basal cell carcinoma
Amelanotic melanoma
Pyogenic granuloma
Histiocytoid hemangioma
You are correct. Excision bx confirmed advanced malignant melanoma by histology. A new neck lump was also identified and FNA confirmed nodal metastasis. Amelanotic melanoma can mimic benign and malignant skin tumors, including pyogenic granuloma, basal cell carcinoma, and inflamed skin tags. Dx can be missed if such lesions aren’t sent for histological exam. Careful search for a hyperpigmented base is imperative to avoid missing a subtle dx of amelanotic melanoma.

BMJ 2021;372:n182