Association between cervical human papillomavirus infection and bladder cancer risk: A community-based cohort study.

BACKGROUND/OBJECTIVES: Few studies have investigated the association between human papillomavirus (HPV) infection and bladder cancer (BLC) risk. This study aimed to evaluate the association between baseline cervical HPV infection and subsequent bladder cancer risk among Taiwanese women over a 30-year follow-up period. METHODS: In this cohort study, we analyzed 4620 women residing in two townships in Taiwan. The study was conducted over a 30-year period, with baseline recruitment occurring between 1991 and 1992, and follow-up continuing up to December 2020. HPV DNA in cervical cells was detected and genotyped using the EasyChip HPV blot. RESULTS: Among 4620 women followed for up to 30 years, 18 developed BLC, including 7 HPV-positive and 11 HPV-negative cases. Infection with multiple HPV types was most prevalent among BLC cases (57.1%), and the incidence of BLC was higher in HPV-positive women (34.1 per 100,000 person-years) compared with HPV-negative women (10.3 per 100,000 person-years). The adjusted hazard ratio for any cervical HPV infection was 2.83 (95% CI: 1.09-7.37; P = 0.033). A higher risk of BLC was observed in participants with multiple-genotype HPV infection (HR = 3.21, 95% CI: 1.01-10.22; P = 0.049) compared with HPV-negative cases, whereas the risk was nonsignificant for single-genotype infection (HR = 2.46, 95% CI: 0.68-8.85; P = 0.168). CONCLUSIONS: This cohort study suggests a possible association between multiple-genotype HPV infection and increased bladder cancer risk; however, given the small number of cases, these results should be interpreted with caution and warrant further validation.