The predominance of human papillomavirus type 16 in vulvar neoplasia.

Southern transfer analysis for human papillomavirus genomic sequences was conducted on 152 vulvar and vaginal tissue specimens obtained from 86 patients. Histopathologic diagnoses included condyloma acuminatum, intraepithelial neoplasia, and invasive cancer. In six patients, lesions of more than one pathologic type were identified. Vaginal lesions constituted less than 5% of tissues examined. Distribution of lesions was as follows: condyloma, 93 lesions from 57 patients; intraepithelial neoplasia, 47 lesions from 29 patients; and invasive carcinoma, 12 lesions from six patients. Seventy-five percent of the patients were white. The mean age of the patients increased from 25 years for condyloma to 38 years for vulvar intraepithelial neoplasia III to 56 years for invasive cancer. A viral diagnosis was made in 81% of condylomas, 84% of vulvar intraepithelial neoplasia III, and 58% of invasive carcinomas. Distribution of viral types differed markedly for the various histopathologies. Types 6/11 accounted for 77% of condylomas and 0% of vulvar intraepithelial neoplasia III. Type 16 was recovered from 12% of condylomas and 81% of vulvar intraepithelial neoplasia III. Type 18 was identified in a small proportion in both categories; type 31 was seen in a few vulvar intraepithelial neoplasia III lesions. In invasive carcinomas, type 16 was the predominantly identified virus. Papillomavirus type 16 emerges as the dominant oncogenic virus in vulvar neoplasms. Its presence in a large percentage of condylomas raises the issue of an "atypical condyloma" as a precursor of neoplasia.