[Safety margins in the excision of primary malignant melanoma. Proposals based on controlled clinical trials]

Abstract

Excisional biopsy is recommended as the procedure of choice whenever there is suspicion of malignant melanoma. Incisional biopsies are only rarely indicated. For nearly seventy years the debate about the optimum resection safety margin around the primary tumor was influenced by historical case reports and paradigms. Recently, controlled clinical studies have provided new insights. Accumulating evidence over the last two decades shows that narrower surgical margins influence neither the rate of satellites or in-transit-metastases nor the occurrence of advanced metastatic disease. Local recurrence is rare (approx. 0.1%) when primary tumors are thin and is seen more often (approx. 10%) in primary tumors of greater thickness (> 4 mm). Analysis of the overall survival in randomized trials shows equal prognosis for malignant melanoma for narrow and wide resection margins. Due to these findings in-toto excisional biopsy for in-situ melanoma, a resection margin of 1 cm for thin primary tumors (< 1 cm tumor thickness) and a resection margin of 1 to 2 cm for primary tumors greater than 1 mm appears sufficient. With these recommendations, primary closure of wounds will be possible in nearly all cases, reducing surgical costs and morbidity. This article should serve as a basis of discussion for the proposed revision of the current guidelines of the German Dermatologic Society (DDG) on the primary surgical care of melanoma patients.