There are limited data on the prevalence and distribution of human papillomavirus (HPV) genotypes in vaginal intraepithelial neoplasia (VAIN). We sought to clarify this issue in a series of 450 VAIN cases with a confirmed diagnosis between 1990 and 2006. HPV genotyping was performed using paraffin-embedded specimens and polymerase chain reaction (PCR)-based methods. Multiple HPV types were validated by E6 type-specific PCR and direct sequencing. The HPV genotypes of the vaginal and cervical neoplasms were compared for those with incident VAIN and a history of previous/concomitant cervical neoplasms. Ki-67 was performed for supporting diagnosis of VAIN. Of these 450 VAIN cases (median age, 59 years; range, 19-93), two with missing paraffin blocks and 54 with poor DNA quality were excluded. HPV was detected in 273/394 (69.3%) VAIN, and multiple infections were found in 17.9% of HPV-positive samples. The leading types were HPV16 (35.5%), HPV58 (9.9%), HPV52 (9.9%), HPV39 (8.4%), HPV33 (7.3%) and HPV53 (7.0%). Among the 156 cases with a history of previous cervical neoplasia, 29.0% had concordant HPV genotypes, while synchronous VAIN samples (n = 49) were more likely to harbor concordant genotypes (58.7%) with the concomitant cervical neoplasm (p = 0.0003). Whether those HPV types in the incident VAIN lesions had existed in the vaginal epithelium at the time of the previous cervical neoplasia or a new acquisition needs to be clarified in prospective follow-up studies.
Copyright © 2011 UICC.