Immunophenotyping of amelanotic melanoma. A case report.

Amelanotic malignant melanoma (AMM) is a subtype of cutaneous melanoma with little or no pigment upon visual inspection. The lack of pigmentation is the reason for late diagnosis of lesions and a poor prognosis. We report a case of a 55-year-old female with an AMM diagnosed by immunophenotyping. Monoclonal antibodies S-100, HMB-45, and antibodies to cytokeratin were used. Our patient underwent a wide local excision (a 2 cm wide margin) 2 years ago. So far there are no signs of a recurrence. In doubtful cases, immunophenotyping with monoclonal antibodies HMB-45 and S-100 is important for confirming the correct diagnosis of AMM.