Objectives To analyze prevalence of HPV DNA, HPV genotype distribution, prognostic factors and long-term outcomes of vulvar carcinoma.

Methods We retrospectively reviewed medical records of patients with vulvar carcinoma who received primary surgeries between 1985 and 2014 in a single institution. General polymerase chain reaction (PCR) SPF1/GP6+ followed by revert-blot detection was performed for human papillomavirus (HPV) genotyping. E6 type-specific PCR of the top-5 prevalent types was performed to reconfirm HPV-negative status. P16INK4a immunohistochemistry staining was performed. Univariate and multivariate analyses were performed to identify predictors of clinical outcomes of squamous cell carcinomas (SCCs).

Results A total of 150 vulvar carcinoma patients eligible for analysis were retrieved. Medial follow up time was 71.4 months (0.2–341.8 months). One hundred and twenty-nine patients (86.0%) were diagnosed as SCC. In SCC specimens, HPV DNA sequences were detected in 56.6%, and 14.3% of non-SCC vulvar cancer (n = 21) were HPV positive. The leading 4 types were HPV16 (54.0%), HPV58 (15.8%), HPV52 (6.6%), and HPV18 (5.3%). HPV-positivity was associated with better 5-year cancer-specific survival (CSS) (P = 0.037). In multivariable analysis, older age (continuous, hazard ratio [HR] 1.06, 95% confidence interval [CI] 1.03–1.08, P <0.001), advanced International Federation of Gynecology and Obstetrics (FIGO) stage (III-IV vs I-II, HR 3.86 95%CI 2.01–7.42, P <0.001) were independent adverse predictors of CSS, while p16-positivity (0.36, 95%CI 0.19–0.69, P =0.002) was related to better prognosis.

Conclusion Advanced FIGO stage and older age were significant adverse predictors, while p16-positivity was a significant factor of better prognosis.