Second Primary Cancers following Anal and Cervical Carcinoma: Evidence of Shared Etiologic Factors

Abstract

The authors examined the incidence of second primary cancers occurring after cervical and anal cancer. Data from the Connecticut Tumor Registry for 1935–1988 and eight other US tumor registries for 1973–1988 were used. Women with primary invasive cervical cancer had a relative risk of 4.6 (95% confidence interval (Cl) 2.4–8.1) for subsequent invasive anal cancer. Increased relative risks after cervical cancer were also found for cancers of the oral cavity (relative risk (RR) =2.2), stomach (RR=1.5), rectum (RR=1.4), larynx (RR=3.4), lung (RR=3.0), vagina (RR=5.6), bladder (RR=2.7), and kidney (RR=1.9); decreased relative risks were noted for melanoma (RR=0.5)and breast cancer (RR=0.8). Patients with a primary diagnosis of anal cancer had relative risks for subsequent invasive and in situ cervical cancer of 1.3 (95%Cl 0.2–4.5) and 3.4 (95%Cl 0.9–8.8), respectively. Anal cancer was also associated with increased relative risk of subsequent lung (RR=2.5) and prostate (RR=1.8) cancers, whereas the relative risk of uterine cancer was 0.2 (95%Cl 0.0–0.9). These findings support other evidence for common factors, such as human papillomavirus infection and cigarette smoking, in the etiology of cervical and anal cancer.