RESUMO
BACKGROUND: Hereditary nonpolyposis colon cancer is associated with a 40-60% lifetime risk of endometrial cancer. Prophylactic hysterectomy is a reasonable management strategy for women who have completed childbearing. We report a case of a woman with hereditary nonpolyposis colon cancer who was found to have an unexpected endometrial cancer at prophylactic hysterectomy. CASE: A woman with hereditary nonpolyposis colon cancer underwent a laparoscopically assisted vaginal hysterectomy and bilateral salpingo-oophorectomy for prophylaxis against endometrial cancer. No unusual intraoperative findings were noted. Pathologic examination revealed a mixed clear cell and endometrioid endometrial carcinoma invading into the myometrium and cervix. The patient underwent a subsequent staging laparotomy, in which no additional disease was found. CONCLUSION: Patients with known hereditary nonpolyposis colon cancer undergoing prophylactic hysterectomy are at risk for having occult endometrial cancer. Gynecologists should consider preoperative endometrial biopsy and intraoperative assessment of the endometrium in these high-risk women.