A single-institutional retrospective analysis of factors related to vaginal intraepithelial neoplasia

BACKGROUND: To date, few studies on the factors related to vaginal intraepithelial neoplasia (VaIN) have been published. In this study, we aimed to analyze the features of VaIN and identify underlying risk factors. METHODS: Patients with VaIN or vaginitis histologically confirmed at the Industrial Street Branch of Chengdu Women’s and Children’s Central Hospital from July 2020 to December 2021 were included. We statistically analyzed their baseline clinical characteristics, human papillomavirus (HPV) infection status, cytology results, and pathology results. Categorical indicators were analyzed using the chi-square test or Fisher’s exact test, as appropriate. Differences were considered to be statistically different with p < 0.05. RESULTS: A total of 62 patients with VaIN (mean age: 39.06 ± 11.66 years) and 32 with vaginitis (mean age: 41.13 ± 13.43 years) were included. Synchronous cervical intraepithelial neoplasia (CIN) was histologically identified in 46 (74.2%) patients with VaIN and 7 (21.9%) with vaginitis (p < 0.001). Low-grade squamous intraepithelial lesions (LSILs) and atypical squamous cells of undetermined significance (ASC-US) were the most frequent cytological abnormalities in both groups. Patients with VaIN only (62.5%) were more likely to be negative for intraepithelial lesion or malignancy than patients with synchronous CIN (32.6%; p = 0.036). No statistically significant difference in HPV infection was noted between patients with VaIN and those with vaginitis (p = 0.439). The most prevalent HPV genotype in patients with VaIN or vaginitis was HPV16, whereas both HPV58 and HPV16 were the most common in patients with concurrent CIN. CONCLUSIONS: Attention should be paid to HPV16- and HPV58-positive patients with cytological abnormalities such as ASC-US and LSILs (especially with synchronous CIN) to avoid misdiagnosis or underdiagnosis and to facilitate early interventions for VaIN.