Human Papillomavirus and Anal Cancer: Prevalence, Genotype Distribution, and Prognosis Aspects from Midwestern Region of Brazil

BACKGROUND: Approximately 90% of all anal cancers are associated with human papillomavirus (HPV), especially high-risk genotypes such as HPVs 16 and 18. OBJECTIVE: To investigate the clinical and prognostic aspects of anal cancers associated with the presence, as well as the genotypic distribution of human papillomavirus (HPV). METHODS: A retrospective study carried out over a 10-year period, using clinical and molecular data, with PCR analysis and reverse hybridization (INNO-LIPA kit), in anal cancers. The data analysis was done using descriptive univariate statistics, and the survival curves were made using the Kaplan–Meier and log-rank methods. RESULTS: Of the 81 formalin-fixed and paraffin-embedded specimens, HPV prevalence was 69% and was significantly higher in squamous cell carcinomas (SCC) than in other anal tumors (p=0.0001). Female patients had a higher prevalence of HPV (p=0.01). Multiple infections were detected in 14.3% of cases. The most prevalent genotypes were HPVs 16, 33, and 18. The overall survival at 60 months was 44.3%, and the prognostic factors included gender (p=0.008) with greater survival for men (52.9%) in comparison to women (29.6%), histological type (p=0.01), SCC (54.4%), adenocarcinomas (37.5%), other carcinomas (14.2%), and the presence of distant metastasis (p=0.01). Survival was not influenced by the presence of HPV (p=0.54). CONCLUSIONS: The association of HPV to anal cancer was found in this study, especially in SCC. However, the presence of HPV did not influence the prognosis of patients with anal cancer.