The results of gynecologic surveillance in families with hereditary nonpolyposis colorectal cancer

OBJECTIVE: We aimed to estimate the incidence rate of endometrial cancer (EC) and to evaluate the results of EC-surveillance in hereditary nonpolyposis colorectal cancer (HNPCC) families.

METHODS: All at-risk women recommended for EC-surveillance by the HNPCC-register-2959 women (19,334women years)-were included. Data on EC-surveillance were available for 871 women (6894women years), who had performed 1945 surveillance visits. The average surveillance period was 7.9 (range 0.1-21.7) years and 46% of the women had had less than 3years between their visits.

RESULTS: During 19,334women years, 60 women with gynecological malignancies or premalignancies were diagnosed. Thirty-nine women had EC. Of these, 31 were from families with identified MMR gene mutations with the median age at diagnosis of 54 (39-83) years (Incidence Rate, IR=0.63 per 100women years) and four women from each Amsterdam (AMS)-positive and AMS-like families (median age 64 (55-73) years, IR=0.06 and 0.05 per 100women years, respectively, p<.0001). Among the 871 surveilled women, 13 EC were found: 7/13 cases were diagnosed by surveillance examination-two as prevalent cancers, diagnosed at the first visit-and 6/13 based on symptoms. In addition, five complex atypical hyperplasias and four ovarian cancers (OCs) were diagnosed. All these women were MMR mutation carriers.

CONCLUSION: Based on 19,334women years of EC-surveillance, our analysis provides a thorough estimation of the EC risk in women with an MMR mutation, or suspected of having Lynch syndrome. We conclude that EC surveillance should only be targeted at MMR-mutation carriers.