Increased risk of renal cell carcinoma subsequent to hysterectomy

In etiological studies of renal cell carcinoma, the associations between ex ogenous hormones, reproductive factors, or gynecological operations have no t been well examined. Our aim was to evaluate gender-specific risk factors for renal cell carcinoma using data from a population-based case-control st udy conducted in Los Angeles, California and to elucidate possible underlyi ng mechanisms. A population-based case-control study involving 422 female r enal cell carcinoma patients, ages 25-74 years, and an equal number of sex- , age-, and race-matched neighborhood controls was conducted in Los Angeles , California. Detailed information regarding reproductive history, hysterec tomy, use of exogenous estrogens, and other medical and lifestyle factors w as collected through in-person interviews. Compared to women with an intact uterus, those who had undergone hysterectomy were at an increased risk for renal cell carcinoma (odds ratio, 1.8; 95% confidence interval, 1.3-2.5), Parity and use of estrogen replacement therapy were no longer risk factors for renal cell carcinoma when hysterectomy was adjusted for in the analysis . No association between renal cell carcinoma and use of oral contraceptive s was found. Limited epidemiological data do not support an endocrine expla nation for the observed hysterectomy-renal cell cancer association. We conj ecture that unintentional injury to the ureter during the surgical procedur e, which results in renal cell damage and consequent renal cell proliferati on, may be a cause of the increased cancer risk in hysterectomized women.