The clinical features of ovarian cancer in hereditary nonpolyposis colorectal cancer

Objective. Hereditary nonpolyposis colorectal cancer (HNPCC) is a hereditar y cancer susceptibility disorder associated with a very high risk for carci noma of the colon and an elevated risk for certain extracolonic cancers inc luding ovarian cancer. Our aim in this study was to describe the clinicopat hologic features of ovarian cancer in HNPCC family members. Methods. Members of the International Collaborative Group on HNPCC collecte d retrospective data on 80 ovarian cancer patients who were members of HNPC C families, including 31 known mutation carriers, 35 presumptive carriers ( by colorectal/endometrial cancer status), and 14 at-risk family members. Results. Mean age at diagnosis of ovarian cancer was 42.7. Nonepithelial tu mors made up only 6.4% of the cancers, and borderline tumors comprised just 4.1% of the epithelial cancers. Among frankly malignant epithelial cases, most cancers were well or moderately differentiated, and 85% were FIGO stag e I or II at diagnosis. Synchronous endometrial cancer was reported in 21.5 % of cases. Conclusions: Ovarian cancer in the general population in severa l clinically important respects. It occurs at a markedly earlier age. It is more likely to be epithelial. If it is a frankly invasive epithelial cance r, it is more likely to be well or moderately differentiated. HNPCC patient s with ovarian cancer are more likely to have a synchronous endometrial can cer than other ovarian cancer patients and are more likely to be diagnosed at an early stage. (C) 2001 Academic Press.