Epidemiology of malignant melanoma in West Germany in an international comparison

Abstract

The incidence and mortality of malignant melanoma (MM) has markedly increased in the Federal Republic of Germany. The data available show a doubling of incidence in the past 15 years and a doubling of mortality in the past 30 years. Germany holds a middle range in the incidence list of MM compared to worldwide data: 6-8 MM were registered per 100,000 inhabitants and year in Germany during the mid eighties, whereas 5 x higher incidences where reported from Australia and the southern states of the USA; incidences higher than 6-8/100,000 where found in the Scandinavian countries. While sun exposure is regarded as the most important risk factor in the international epidemiology of MM, a relationship between sun exposure and increasing risk of MM could not be clearly established for the German population. In contrast, the total number of melanocytic nevi (MCN) and the occurrence of dysplastic nevi where found to be significant markers of an increased relative risk for developing MM in the German population. The increase of the relative risk was 16 x for persons with greater than 60 MCN compared to individuals with greater than or equal to 10 MCN and there was an additional 7 x increase of the relative risk for persons with greater than or equal to 1 dysplastic nevus. The course of the disease is lethal in most cases of metastatic malignant melanoma. 90% of all patients in the Federal Republic of Germany, however, were first diagnosed in clinical stage I (= primary tumor alone) and the average 10 years survival rate was 70% in the time period since 1970. Multivariate regression analysis revealed that the most important prognostic factors in stage I MM were tumor thickness and sex. This finding should be taken into consideration for a prognostic classification of stage I MM.