The association of pre-treatment HPV subtypes with recurrence of VIN.

OBJECTIVE: To assess whether pre-treatment HPV types are associated with recurrence of high-grade vulvar intraepithelial neoplasia (VIN2+).

STUDY DESIGN: Data of consecutive patients with pretreatment HPV DNA test undergoing treatment for VIN2+ were retrospectively collected. Risk factors promoting the risk of VIN2+ persistence and recurrence were analyzed using Kaplan-Meier and Cox hazard proportional models.

RESULTS: 64 patients had pretreatment vulvar-vaginal HPV DNA test. Two were excluded due to the presence of synchronous vulvar cancer, thus leaving 62 patients for the final analysis. HPV16, HPV18, HPV31 and HPV33 were the most common HPV genotype detected, occurring in 15 (24.2%), 4 (6.5%), 8 (12.9%) and 5 (8.0%) patients, respectively. HPV was not detected in 19 (30.6%) patients. During a mean (SD) follow up of 56.7 (±26.7) months, 10 (16.1%) patients had VIN2+ persistence/recurrence. Mean (SD) lesion-free interval was 51.7 (±31.4) months. Via multivariate analysis, pretreatment infection from HPV31 (HR:46.7(95%CI:4.21,518.4); p=0.02) and HPV33 (HR:77.0(95%CI:6.73,881.9); p<0.001) correlated with an increased risk of VIN2+ persistence/recurrence. Additionally, we observed that patients undergoing surgical excision followed by LASER ablation experienced a trend towards lower recurrence rate than patients undergoing other surgical or medical treatments (HR:0.20(95%CI:0.03,1.09); p=0.05). Two (3.2%) patients developed progression to vulvar cancer.

CONCLUSIONS: Owing to the inherent biases of the retrospective study design and the small sample size, our data have to be corroborated by larger and prospective studies. HPV31 and HPV33 have a potential role in predicting VIN2+ persistence/recurrence. These findings will be paramount, owing to the implementation of new immunization programs.