Site distribution of cutaneous melanoma in Queensland.

The age-adjusted incidence rates of cutaneous melanoma in Queensland in 1987 have been analysed for 16 anatomic sites, taking into account their surface areas. In men, the incidence of invasive melanoma on the ears, a chronically sun-exposed site, was extraordinarily high with annual rates of over 200 per 10(5) units of surface area in the Queensland population. Next highest rates of over 100 melanomas per 10(5) units were found on the face, neck, shoulders and back in men and the face and shoulders in women. Comparison with site-specific incidence rates in the same population 7 1/2 years previously showed that incidence of invasive disease had significantly increased for all these sites, though the largest relative increase in this period occurred on the forearm in both men and women. Melanoma was very rare on the buttocks of both sexes and on the scalp in women, sites which receive the least sun exposure. These findings are consistent with the theory that excessive total sun exposure plays a major role in the aetiology of cutaneous melanoma.