Risk of cancer in relatives of patients with cutaneous melanoma
Cutaneous malignant melanoma (CMM) is a recognized feature of the Lynch type II cancer-family syndrome and the Li-Fraumeni's syndrome. A significant contribution of these syndromes to the total burden of CMM would be reflected in an increased risk of nonmelanoma cancers in first degree relatives. Pedigrees were taken from 85 patients with CMM using a family history questionnaire. The relative risk of death from all cancers and individual cancers in first degree relatives was calculated. Of the 85 questionnaires, those of 79 patients were completed and of adequate quality for analysis. The first degree relatives of CMM patients showed no increased risk of cancer death, the relative risk of cancer death being 1.0. Six patients (7.6%) had first degree relatives with CMM. One patient had a family history compatible with the dominant transmission of a predisposition to cancer. It is important to establish whether an increased cancer risk is present in relatives of patients with malignancies so that screening programs may be offered. This study provides little evidence to support seeing relatives for noncutaneous malignancies in the absence of a dominant family history of predisposition to cancers. The increased frequency of CMM in relatives suggests that relatives of CMM patients should be counseled on protection from the sun and examination of the skin for melanoma.