The clinical diagnosis of malignant melanoma.

The diagnosis of malignant melanoma thus rests upon an appreciation of sometimes subtle but definite signs detectable by careful observation of color, border, and surface of the lesions. Differential diagnosis lies among several cutaneous lesions, neoplastic and nonneoplastic. At times the lesions that are most difficult to distinguish from malignant melanomas are certain pigmented basal cell carcinomas, thrombosed hemangiomas, and certain types of moles. An attempt has been made in this review to describe and illustrate those features of pigmented lesions that are most helpful in diagnosis.