Malignant melanoma in the elderly.

Abstract

Advancing age is associated with poorer prognosis in malignant melanoma. We studied 3,872 cases of malignant melanoma to evaluate whether the effect of age could be analyzed relative to sex, tumor depth, primary site, and other clinical and pathologic variables. The sex distribution by age shows a slight female predominance in the early and late decades but male predominance in the middle years. The percentage of patients with metastatic disease at initial diagnosis did not vary with age, despite greater diameter and depth of lesions in the older patients. In fact, in the older age groups, initial nodal metastasis occurred slightly less frequently. Trunk primaries decreased in frequency with increasing age, while extremity lesions remained relatively constant, and face, nose, and ear lesions increased. This was in part related to the histopathologic type, as lentigo maligna lesions increased in frequency with age, superficial spreading lesions were somewhat less frequent in the older age group and nodular types were fairly constant. On the basis of both Clark's level and Breslow thickness, there was an increasing proportion of deeper penetrating lesions in the older age group. The mean diameter of these lesions on the skin surface was also greater for the older patients. This would suggest that lesions in the older individual remain confined to the local site longer, penetrate and spread, but do not necessarily metastasize more rapidly. Cox model regression analysis of survival time within stage showed that age was highly significant as a poor prognostic factor. Though the adverse relation of advancing age with survival was partially explained by predominance of other unfavorable factors, such as primary site, depth of lesion, or histologic type, age remained an independent poor prognostic factor (chi 2 = 5.3; P = .02) for death due to melanoma.