Hereditary aspects of endometrial adenocarcinoma.

The importance of heredity in the etiology of endometrial cancer (EC) was examined in a series of 326 patients with EC diagnosed at age 60 years or less. If one or both of the proband's parents had died of cancer, a thorough family history of malignancies was studied. Altogether 291 cases with complete parental data were found. Nine kindred (3.1%) showed features compatible with the dominantly inherited cancer trait known as hereditary non-polyposis colorectal cancer (HNPCC). In another 9 cases, clustering of malignancies in 2 or more successive generations was indicative of familial cancer. Aspecific cancer aggregates were found in 112 probands' families, and family history was negative in 161 cases. No families had gynecological cancer as the only malignancy. HNPCC, the genetic etiology of which was recently revealed, seems to be an important risk factor for EC, indicating the significance of family-history investigations of all patients with EC. Colorectal carcinoma (CRC) was here associated with EC also in families with clusterings of malignancies, but in these families no typical features of any known hereditary cancer syndrome could be found. On the basis of the results of the present study, proper surveillance for colorectal cancer should be recommended for patients with endometrial carcinoma if they belong to a family with features indicative of HNPCC. Furthermore, healthy gene carriers in an HNPCC family also need careful surveillance for CRC, EC and perhaps for other extra-colonic malignancies typical for HNPCC. Prophylactic surgery should even be considered in these cases.