[Risk factors for the development of malignant melanoma in West Germany. Results of a multicenter-case control study].

In this multicenter case-control study (1,079 melanoma patients, 778 control persons), the significance of the well-known risk factors for the development of malignant melanoma (MM) was assessed for a German population. The multifactorial analysis of the data confirmed the total number of melanocytic nevi (MCN) as the most robust indicator for an increased melanoma risk. For persons with more than 50 MCN the relative risk was 4.8 times as high as for persons with fewer than 10 MCN. Hair color was found to be another valuable indicator. In persons with red hair the risk of MM was 4.7 that in individuals with black hair. Remarkably fair persons with skin type 1 (always sunburn, never tanning) had two times the risk of that in persons with skin type 4 (never sunburn, always tanning). The habit sun bathing for recreation showed no influence on the development of melanoma. A 2.7 x increased melanoma-risk was detected in persons with occupational sun exposure and out of doors work.