Early invasive and in situ warty carcinoma of the vulva: clinical, histologic, and electron microscopic study with particular reference to viral association.

Cases of carcinoma of the vulva with a warty appearance were reviewed. Altogether, 27 cases of warty carcinoma of the vulva were treated at the University of Minnesota Hospitals between 1976 and 1980, which accounted for 22.4% of all vulvar epithelial malignancies. As compared to the previous experience between 1951 and 1970, this relative frequency increased fourfold. Clinical history indicated that warty carcinoma of the vulva was not necessarily preceded by long lead periods of in situ lesions. The lesions seemed to occur in all ages after adolescence, were multifocal in one third of the cases, were frequently locally recurring, and were relatively benign despite their often large size. Many of them were originally diagnosed as condyloma acuminatum. Virus-like particles were seen in eight of the 12 cases (67%) examined with transmission electron microscopy, which included six cases of invasive lesions. These observations suggest that human papillomavirus (HPV) may be the important etiologic agent of this group of tumors. Warty carcinoma of the vulva must be clearly separated from conventional invasive squamous cell carcinoma of the vulva, as its clinical behavior and a possible etiology appear unique.