Risk of Renal Cell Carcinoma After Hysterectomy

Background: Hysterectomy is the most common gynecologic operation among women; study findings indicate that hysterectomy is associated with renal cell carcinoma. Methods: To assess the effects of hysterectomy on the incidence and risk of renal cell carcinoma, we performed a population-based cohort study using data from 184 945 women who had undergone hysterectomy (hereafter referred to as women with hysterectomy) and from 657 288 matched women who had not undergone hysterectomy (hereafter referred to as women without hysterectomy) by linking nationwide Swedish health care registers, including the Swedish Inpatient Register and the Swedish Cancer Register (January 1, 1973, through December 31, 2003). Risk of renal cell carcinoma owing to hysterectomy status was assessed using Cox proportional hazards regression models with hazard ratios (HRs) and 95% confidence intervals (CIs). Results: The crude incidence rates of renal cell carcinoma were 17.4 cases per 100 000 person-years among women with hysterectomy and 13.1 cases per 100 000 person-years among women without hysterectomy. This corresponded to an adjusted overall HR of 1.50 (95% CI, 1.33-1.69) for renal cell carcinoma among women with hysterectomy vs women without hysterectomy. The risk of renal cell carcinoma was age dependent, and the highest risk was found within 10 years of surgery among women who underwent hysterectomy at age 44 years or younger (HR, 2.36; 95% CI, 1.49-3.75). The overall risk of renal cell carcinoma after hysterectomy was consistently increased and of similar magnitude over the time strata: HR, 1.50 (95% CI, 1.26-1.78) for years 0 to 10; 1.49 (1.2.2-1.82) for years 11 to 20; and 1.51 (1.05-2.16) for more than 20 years after surgery. Conclusions: Hysterectomy for benign indications was significantly associated with renal cell carcinoma. Women undergoing the procedure at a young age were at particular risk.