Pseudobowenoid change of the vulva: a histologic variant of untreated condylata acuminatum.

Vulvar condylomata are distinguished from vulvar intraepithelial neoplasia by orderly maturation, a low mitotic index, and the absence of nuclear atypia in the lower epithelial layers. Podophyllin therapy might produce changes in condylomata mimicking vulvar intraepithelial neoplasia but can be distinguished, particularly with a recent history of podophyllin use. This report describes five patients with vulvar condylomata that morphologically resemble both podophyllin effect and vulvar intraepithelial neoplasia. The mean age was 30.5 years. All lesions exhibited superficial keratinocytes in various stages of apoptosis, with a spectrum of nuclear degenerative changes characterized by absence of the nuclear membrane and dispersed nuclear chromatin. The characteristic finding was a perichromatin halo delineated by a rim of dense cytoplasm, beyond which a second zone of uniform clearing was observed, similar to changes noted in vulvar intraepithelial neoplasia. There was an absence, however, of either nuclear atypia in the lower cell layers or apoptosis and mitotic arrest observed in vulvar intraepithelial neoplasia and podophyllin therapy. Two (50%) of four lesions tested positive for human papillomavirus nuclei acids, one by polymerase chain reaction and the other by DNA-DNA in situ hybridization. No common human papillomavirus types were found. Pseudobowenoid change might represents a distinct type of vulvar condyloma, perhaps related to an unusual human papillomavirus.