Occult ovarian tumors in women with BRCA1 or BRCA2 mutations undergoing prophylactic oophorectomy.

PURPOSE: To review the findings at prophylactic oophorectomy of a series of women who presented to a familial breast and ovarian cancer clinic. MATERIALS AND METHODS: Data from medical charts, operative notes, and pathology reports were collected on women who had undergone prophylactic oophorectomies because of the elevated risk of ovarian cancer. Because only a subset of patients underwent BRCA1 and BRCA2 testing, each patient's risk of hereditary predisposition was calculated using the Berry-Parmigiani model and family history data. RESULTS: From June 1989 to December 1998, 50 women seen at our clinic underwent prophylactic oophorectomy, 33 of whom had a calculated risk of carrying a germline BRCA1 or BRCA2 mutation greater than 25%. Among this group, four incidental tumors were found (four of 33, or 12%); one tumor was noted at the time of surgery and three were noted only in the final pathology. Two patients had microscopic, poorly differentiated serous adenocarcinomas in multiple sites on both ovaries. A third patient had a bilateral serous borderline tumor with micropapillary features. The fourth patient had a microscopic serous borderline ovarian tumor. All four patients had germline BRCA1 or BRCA2 mutations, and three had unremarkable transvaginal ultrasonography examinations within 6 months before prophylactic surgery. CONCLUSION: Foci of malignant tumor are not uncommon in prophylactic oophorectomies performed in women at very high risk for ovarian cancer and may not be detected on ultrasonograms. Surgeons should have a high suspicion of finding cancer in these women at the time of prophylactic surgery, and careful pathologic assessment of the specimens should be conducted.