Occurrence of glioblastoma multiforme in three generations of a cancer family.

We report a cancer family in which glioblastoma multiforme occurred in each of three successive generations and strictly in the paternal lineage. The pedigree is consistent with an autosomal-dominant pattern of inheritance, and this conclusion is supported by the incidence of other tumors within the family. Ten of the 23 blood relations of the proband have developed cancers (43.5%), and 5 of these have been breast carcinomas. The clinical importance of the cancer family syndrome is discussed, as is the relevance of genetic factors in the expression of the neoplastic phenotype.