Prevalence and genotyping of high-risk HPV in bladder cancer patients from Pakistan

Abstract

Human Papillomavirus (HPV) is a sexually transmitted epitheliotropic virus that infects the anogenital tract. High-risk HPV (HR-HPV) genotypes significantly increase risk of cervical, anal, vulvar, vaginal, and penile carcinomas. So far no significant etiological association has been established between HPV and bladder cancer therefore, the current study aimed at evaluating the overall prevalence of HPV in bladder cancer patients along with main focus on the genotype 16 and 18, with respect to Pakistani population. The study included 63 bladder cancer participants, demographic data and biopsy samples along with the histopathological reports were collected with patients’ consent. DNA was extracted and processed for HPV detection using L1 consensus primers. HPV genotyping was carried out using E6-E7 specific primers for HPV16 and 18, via conventional PCR. This study showed that 15.9% (10/63) of bladder cancer cases were HPV positive. Upon genotyping, prevalence rate for HPV16 was 4.8% (3/63), HPV18 was 9.5% (6/63) and other HR-HPV genotype was 1.6% (1/63). Histologically, most of the HPV positive cases were of low grade papillary urothelial carcinoma and urothelial carcinoma. The HPV male to female incident ratio was 9:1 with an average age of 65.5±11.8 years. The study showed no significant association of tobacco consumption, physical activity and co-morbidities (diabetes and hypertension) in HPV positive bladder cancer patients. In conclusion, the present study provides the latest epidemiological data related to HPV prevalence and genotype distribution in bladder cancer. The results indicate an association of HPV with bladder cancer, with HPV18 genotype being more prevalent. The study emphasizes that HPV is a serious issue in low- and middle-income countries where existing methods of prevention are still inadequate or costly. It is imperative to implement local HPV screening programs to help lower the burden of HPV-induced carcinomas.