Naevoid melanoma is an uncommon subtype of malignant melanoma
of the skin that closely mimics architectural and cytological features of a benign compound or intraepidermal naevus. It involves the dermis and has the potential for metastasis. Histologically, areas of sheetlike confluent melanocytic proliferation in the dermis are typical; the malignant cells are generally epithelioid.
Most naevoid melanomas are found on the trunk and proximal extremities. The lesions are generally papular, nodular, or verrucous, and laterally sharply demarcated; they often reach 5-10 mm in diameter.
Naevoid melanomas account for approximately 1-2% of all cutaneous melanomas. They occur in all age groups, but most frequently in young to middle-aged adults. Prognostic factors are tumour thickness, mitotic rate, and large cell type. Overall, the prognosis is similar to that of classical malignant melanoma
LeBoit PE, Burg G, Weedon D, Sarasin A (Eds.)
World Health Organization Classification of Tumours. Pathology and Genetics of Skin Tumours
IARC Press: Lyon 2005