Occurrence of melanomas on the upper and lower limbs in eastern Australia.

Abstract

In view of the changing trends in the incidence of melanoma at different body sites and in particular on the limbs, the detailed distributions of over 10,000 invasive melanomas diagnosed on the upper and lower limbs in residents of mainland eastern Australia between 1987 and 1993 were examined. Cancer notifications and histopathology reports from the cancer registries of Queensland, New South Wales and Victoria were searched manually, and subsites when specified were recorded as shoulder, upper arm, forearm, elbow, wrist or hand, and thigh, leg, knee, ankle or foot. On the upper limbs relative tumour densities were highest on the shoulder, approximately equal on the upper arm and forearm and least on the hand in both men and women; on the lower limbs melanomas occurred more than twice as often on the leg than on the thigh or the foot, taking account of surface area. There was a clear inverse gradient of incidence of melanoma with latitude in the three eastern Australian states studied, but little difference between the states or between sexes in distribution of histological type: the majority specified being specified as superficial spreading melanomas. In contrast to predictions based on apparent frequency of sun exposure at subsites on the upper limbs, the relative concentration of melanomas on the shoulder suggests that wearing sleeveless garments outdoors in the sun should be avoided whenever possible. Also, the similar densities of leg and forearm melanomas seems inconsistent with the relative degree of exposure of each and further suggests that women's adoption of ankle-length skirts or trousers, in preference to knee-length skirts would be a worthwhile modern control measure.