Human papillomavirus DNA determination of anal condylomata, dysplasias, and squamous carcinomas with in situ hybridization.

Infection with types 6, 11, 16, and 18 of the human papillomavirus (HPV) is associated with condylomatous, dysplastic, or carcinomatous changes in the genital tract. Emerging evidence suggests that a similar series of lesions develops in the anal canal after exposure to the same HPV types. In situ hybridization was performed with the use of biotinylated DNA probes to HPV 6, 11, 16, and 18, so as to determine the frequency of HPV DNA in 45 perianal and/or anal condylomata, 6 anal intraepithelial neoplasias, and 13 anal squamous cell carcinomas. Of the 33 perianal and/or anal condylomata in which HPV DNA was detected, 13 contained HPV 6 and 11, 12 HPV 6, 7 HPV 11, and 1 HPV 6, 11, and 18. Two of four severe anal dysplasias contained HPV 16, whereas one case each of mild and moderate anal dysplasia contained HPV 6. No HPV DNA was detected in the anal squamous cell carcinomas. The study demonstrated the presence of HPV DNA in 73% of condylomata and 67% of anal dysplasias. The observations suggest that the cloacogenically derived anal epithelium is susceptible to infection by the same HPV types as infect the similarly derived epithelium of the lower female genital tract and that these HPV types result in some similar lesions, i.e., condylomata and dysplasias in both sites. A role in the genesis of anal cancer was not found in this study.