Case-control study of in situ and invasive carcinoma of the vagina.

A case-control study of 41 patients with carcinoma in situ (CIS) or invasive cancer of the vagina and 97 community controls was undertaken to identify potential risk factors. Although vaginal and cervical cancers often occur as multiple primaries, only a few common risk factors prevailed. Similar to cervical cancer, low education and family income were risk factors for vaginal CIS and invasive cancer. In addition, history of genital warts was strongly related (RR = 2.9), although other sexual factors were not. Previous genital abnormalities related to subsequent cancer risk, with significant associations seen for vaginal discharge or irritation (RR = 6.1), a previous abnormal Pap smear (RR = 3.8), or an early hysterectomy (RR = 6.7). In addition, there was some evidence that vaginal trauma might be involved, with nonsignificant and independent associations relating to regular douching with preparations other than water or vinegar (RR = 2.7) and frequent washing of the genital area (RR = 2.7). Further studies are needed to determine whether our findings persist among a larger series of cases.