Unlocking the secrets: Exploring the connection between HPV and bladder cancer in Pakistan

Abstract

Background: Human Papillomavirus' (HPV) clear association with anogenital carcinomas raises concerns about its role in urologic carcinomas due to anatomical proximity. This etiological link is under-researched in Pakistan, creating a critical gap in the literature.

Objectives: To decipher any probable pathological association of high-risk HPV genotypes in bladder cancer etiology.

Methods: Bladder biopsies from 63 bladder cancer patients, confirmed by H&E and IHC staining were collected with histopathological and clinical data, after informed consent. DNA was extracted and processed for HPV detection using L1 consensus primers. HPV genotyping was performed using E6-E7 specific primers for HPV16 and 18, via conventional PCR.

Result: About 15.9% (10/63) of bladder cancer cases were HPV-positive. 30% (3/10) of which were HPV16-positive, 60% (6/10) were HPV18-positive, while the remaining 1 sample (1/10) was neither positive for HPV16 nor 18 indicating a probable involvement of other high-risk genotypes. Histologically, most of the HPV-positive bladder cancers were low-grade invasive urothelial carcinoma, having a male-to-female incident ratio of 9:1 with an average age of 65 years. No significant association was found between HPV prevalence and tobacco consumption, physical activity, co-morbidities (diabetes and hypertension), and treatment effectiveness.

Conclusion: The study provides the latest epidemiological data on the prevalence and genotype distribution of HPV in bladder cancer in Pakistan. Although the frequency of HPV was not so high, nonetheless an association with bladder cancer incidence was identified as an important risk factor. Consequently, HPV remains a serious issue in low- and middle-income countries (LMICs), significantly contributing to otherwise preventable cancers.

Keywords: Bladder Cancer; HPV; HPV16; HPV18; STI.