OBJECTIVE: To estimate ovarian and peritoneal cancer rates after hysterectomy with and without salpingo-oophorectomy for benign conditions.
METHODS: All patients after hysterectomy for benign disease from 1988 to 2006 in Kaiser Permanente Northern California, an integrated health organization. Incidence rates per 100,000 person-years were calculated.
RESULTS: Of 56,692 patients, the majority (54%) underwent hysterectomy with bilateral salpingo-oophorectomy; 7% had hysterectomy with unilateral salpingo-oophorectomy, and 39% had hysterectomy alone. There were 40 ovarian and eight peritoneal cancers diagnosed during follow-up. Median age at ovarian and peritoneal cancer diagnosis was 50 and 64 years, respectively. Age-standardized rates (per 100,000 person-years) of ovarian or peritoneal cancer were 26.7 (95% confidence interval [CI] 16–37.5) for those with hysterectomy alone, 22.8 (95% CI 0.0–46.8) for hysterectomy and unilateral salpingo-oophorectomy, and 3.9 (95% CI 1.5–6.4) for hysterectomy and bilateral salpingo-oophorectomy. Rates of ovarian cancer were 26.2 (95% CI 15.5–37) for those with hysterectomy alone, 17.5 (95% CI 0.0–39.1) for hysterectomy and unilateral salpingo-oophorectomy, and 1.7 (95% CI 0.4–3) for those with hysterectomy and bilateral salpingo-oophorectomy. Compared with women undergoing hysterectomy alone, those receiving an unilateral salpingo-oophorectomy had a hazard ratio (HR) for ovarian cancer of 0.58 (95% CI 0.18–1.9) and those undergoing bilateral salpingo-oophorectomy had an HR of 0.12 (95% CI 0.05–0.28).
CONCLUSIONS: The removal of both ovaries decreases the incidence of ovarian and peritoneal cancers. Removal of one ovary might also decrease the incidence of ovarian cancer but warrants further investigation.
LEVEL OF EVIDENCE: II
The removal of ovaries decreases the incidence of ovarian and peritoneal cancers; the removal of one ovary also might decrease ovarian cancer, but this warrants further investigation.
Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Sciences, Helen Diller Family Comprehensive Cancer Center, and the Division of Gynecology, Department of Obstetrics and Gynecology and Reproductive Sciences, University of California, San Francisco School of Medicine, San Francisco, the Division of Research, Kaiser Permanente, Oakland, the Division of Medical Oncology, Chao Comprehensive Cancer Center, University of California, Irvine—Medical Center, Chao Family Comprehensive Cancer Center, Orange, and the Division of Epidemiology, Stanford Cancer Center, Stanford University School of Medicine, Stanford, California.
Corresponding author: John K. Chan, MD, Division of Gynecologic Oncology, Department of Obstetrics, Gynecology, and Reproductive Sciences, UCSF Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco School of Medicine, 1600 Divisadero Street, Box 1702, San Francisco, CA 94143-1702; e-mail: email@example.com.
Funded by the National Institute of Health, Grant Number 1R03AG032602-01, and The John A. Kerner Research Fund.
Financial Disclosure The authors did not report any potential conflicts of interest.