CUTANEOUS MALIGNANT-MELANOMA IN TEENAGERS

Of 57 reviewed cases of malignant melanoma in teenagers, 51 had a mini mum follow-up of 5 years. The histological and some clinical features of the 51 cases were compared for diagnostic and prognostic significan ce with those of 19 Spitz naevi and 10 other benign naevi using the SP SS-X computer program. The overall crude survival was 71% (males 64%, females 81%). Five patients with regional metastases survived more tha n 5 years, three of these more than 10 years. The main statistically s ignificant features associated with a poor prognosis were Breslow thic kness, diameter of ulcer, abnormal mitoses, pushing dermal borders and marginal (deep) mitoses. In comparison with Spitz naevi, features fav ouring malignancy were Breslow thickness, fine dusty cytoplasmic melan in pigment, marginal or abnormal mitoses, epithelioid intra-epidermal melanocytes below parakeratosis, dermal nests larger than junctional n ests and the mitotic rate in the papillary dermis. Features favouring a benign lesion were diffuse maturation, spindle cells, spindle nuclei and Kamino bodies, especially if numerous or clustered. In comparison with the atypical benign naevi, significant features favouring malign ancy were marginal or abnormal mitoses, single cell epidermal invasion below parakeratosis, large nuclei and irregular nuclei.