Human papilloma virus infection and overexpression of p53 protein in bilharzial bladder cancer

Aims and background: An association between human papilloma virus (HPV) and bladder cancer has been reported. However, the role of HPV in bilharzial bladder cancer and its prevalence have not yet been clarified. Study design: We investigated 50 cases for HPV types 16/18 by in situ hybridization. Also, p53 protein expression by immunohistochemistry was evaluated in 41 of the 50 cases, with correlation of these factors to clinicopathologic parameters and tumor relapse after primary treatment. Results: HPV was detected in 46% of Egyptian bladder carcinomas (23/50 cases). Positivity was 47.8% for squamous cell carcinoma and 36.4% for transitional cell carcinoma. There was a possible viral-bilharzial association as 52.8% of Bilharzial cases, whereas only 12.5% of non-Bilharzial cases were HPV positive (P < 0.05). P53 protein was found in 19/41 (46.3%) cases. There was a concordance between HPV and p53 in 58.5% of cases. Neither factor was related to tumor recurrence after primary treatment. Conclusions: HPV may thus be implicated in the etiology of bilharzial bladder cancer, but a definite causal relationship remains to be demonstrated. HPV together with p53 alterations work in synergy to accelerate the carcinogenic process, as there was concordance in the results of both parameters in 24/41 (58.5%) cases.