Sexual factors and prostatic cancer: results from a case-control study.

A case-control study of a number of factors of possible etiologic significance for prostatic cancer was conducted in the Minneapolis-St. Paul area. The focus was primarily on sexual factors. Two hundred and fifty incident cases of prostatic cancer, 238 hospital controls, and 240 neighborhood controls were included. Controls were matched to cases on age, sex, and race. Cases were somewhat more educated than controls. An association was found between prostatic cancer and a history of venereal disease in their sexual partners: odds ratio (OR) = 2.71, 95% confidence interval (CI) = 1.14 to 6.46 and OR = 2.09, 95% CI = 1.02 to 4.29 for hospital and neighborhood controls, respectively. Cases had more sexual experiences with prostitutes, although their overall lifetime frequency of sexual intercourse with all partners was somewhat lower. Cases also reported more homosexual partners than controls. The results from the study lend some support to an infectious hypothesis for prostatic cancer. The lower frequency of sexual intercourse (OR = .54, 95% CI = .34 to .83 and OR = .68, 95% CI = .47 to 1.01 for hospital and neighborhood controls, respectively) is also noteworthy and may be indicative of a hormonal difference related to sexual interest or drive.