Human papillomavirus prevalence and type distribution in penile carcinoma

Background: Penile carcinoma is an uncommon and potentially mutilating disease with a heterogeneous aetiology. Several risk factors have been established for its development. Human papillomavirus (HPV) infection seems to play an important role in the development of a subset of these carcinomas and its presence is thought to be related to the histological type. HPV prevalence in penile tumours is reported to be associated to a variety of morphological changes. Its determination will provide a better estimate for HPV related cancer burden and its preventable fraction. Methods: A systematic and comprehensive literature review of the major penile cancer studies published from 1986 until June 2008 evaluating the HPV prevalence among the different histological types was carried out. Results: 31 studies including 1466 penile carcinomas were reviewed. Global HPV prevalence was 46.9%. Relative contribution was: HPV-16 (60.23%), HPV-18 (13.35%), HPV-6/11 (8.13%), HPV-31 (1.16%), HPV-45 (1.16%), HPV-33 (0.97%), HPV-52 (0.58%), other types (2.47%). Assessment of multiple infections contribution is limited due to study design. Basaloid and warty squamous cell carcinomas were the most frequent HPV-related histological types, but keratinising and non-keratinising subtypes also showed prevalence rates of around 50%. Conclusions: About half of the penile tumours were associated with HPV 16-18 with little presence of other genotypes. Research on the mechanisms behind penile carcinogenesis is warranted. Available HPV vaccines are likely to be effective in penile tumours.