Malignant melanoma is a neoplasm whose course is capricious and unpredictable. Even the most experienced eye encounters difficulty in early recognition of this tumor. The three examples of melanoma on this page are variations from the usual pattern and in each instance provide the clinician with important information. Proper management depends on accurate interpretation of this information.
Amelanotic melanoma (Fig 1) differs from pigmented melanomas only in that the melanocytes do not produce melanin. Highly malignant, this erythematous or flesh-colored nodule arouses suspicion by its erosion and destruction of normal cutaneous structures. Neither more nor less malignant than its pigmented counterpart, the amelanotic lesion is particularly dangerous because it is often unrecognized.
Juvenile melanoma (Fig 2) occurs in prepubertal children and represents a melanocytic nevus which is undergoing such rapid evolution that the microscopic appearance suggests malignancy. These tumors are benign with very rare exceptions. Interpretation by an experienced pathologist