Familial multiple myeloma: report of fifteen families

To further define the frequency, clinical and biological features of famili al multiple myeloma we performed a retrospective study of related patients who presented with multiple myeloma. Most cases of familial multiple myelom a were observed in siblings (10/15), in whom the mean age at diagnosis was similar to unrelated multiple myeloma. In successive generations the mean a ge at diagnosis was lower. Monoclonal component was identical (IgG kappa) i n seven families. Familial history of monoclonal gammopathy of undetermined significance was observed in three families. Five other prospective studie s of 1263 patients identified four affected families (3.2 per 1000 cases of multiple myeloma), and raise the question of a genetic background in multi ple myeloma.