Malignant melanoma in Scotland 1979-1983.

1318 cases of primary malignant melanoma of the skin first presenting in Scotland in the years 1979-83 and registered with the Scottish Melanoma Group are described. The annual age-adjusted incidence rate is 4.75 per 100 000 for females and 2.77 per 100 000 for males. Incidence rose by an annual average of 2.5% over the five-year period. The female: male ratio was 2:1, and 48.5% of all cases were of the superficial spreading histogenetic variety. Five-year survival rates for the patients registered in 1979 confirm the prognostic value of the tumour-thickness (Breslow) measurement. They were 93% for patients with tumours less than 1.5 mm thick (39% of patients), 67% for those with tumours 1.5-3.49 mm thick (30%), and 37% for those with tumours thicker than 3.5 mm (31%). This study shows that methods for early recognition of thin tumours should be encouraged.