Background and Objective: Anal squamous proliferative lesions, including condyloma, anal high-grade squamous intraepithelial lesion (AHSIL) and squamous cell carcinoma (SCC), are associated with human papilloma virus (HPV) infection. The objectives of the study were to investigate the HPV prevalence of anal squamous proliferative lesion in Taiwan.
Study Design: From 1991 to 2005, 41 cases with condyloma, 12 cases with AHSIL, and 13 cases with SCC were collected. DNA was extracted from the tissue sections of these patients, and the HPV genotype was identified using polymerase chain reaction and gene chip. The integration status of HPV16 DNA was also evaluated by quantitative real-time polymerase chain reaction.
Results: Anal condyloma mainly occurred in young males, but AHSIL and anal SCC developed in older patients. In the patients with human immunodeficiency virus (HIV) infection, AHSIL developed much earlier than patients without HIV infection (36 vs. 61 years). HPV DNA was detected in all 56 patients whose specimens contained adequate DNA. High-risk HPVs (type 16, 58, etc.) were mainly detected in the AHSIL and SCC. Multiple HPV infection was found in AHSIL (4 of 12) and condyloma (11 of 34) but was rare in invasive cancer (1 of 12). Seven of 8 patients with HPV16 infection had coexistent episomal and integrated forms.
Conclusion: HPV58 is a unique high-risk HPV prevalent in Taiwan. The integration status of HPV seems not correlated with the severity of the dysplasia. In our study, emerging HIV-positive AHSIL in recent years indicates that we should devote more efforts to promote sexual safety among the people who engaged in anal intercourse.