Even if vulvar cancer is not common, over one hundred women are affected in Austria per year. There is strong evidence that basaloid and warty variants are associated with types of human papillomavirus (HPV).
The aim of this study is to analyze the types of HPV in vulvar cancer in Austria. This cross-sectional period-prevalence international collaborative study on archival specimens was performed in cooperation with the Institut Catalan di Oncologia in Barcelona, Spain. A total of 177 consecutive samples of Austrian women were analyzed to detect the presence of various HPV types using the SPF10 PCR/DEIA/LiPA25 system. Furthermore, the expression of the tumor suppressor protein p16INK4a was analyzed by immunohistochemistry (CINtec histology kit, ROCHE). A tumor was considered HPV-driven if an overexpression of p16INK4a was detected.
In all, 41 cases of vulvar cancer tested positive for HPV DNA (23%) and 32 (18%) were p16 positive. Patients with warty and basaloid squamous cell cancer were significantly younger than those with keratinizing squamous cell cancer (63.3 years vs. 71.0 years, p = 0.021). In addition, 77.4% of all cases suffering from warty or basaloid squamous cell cancer tested positive for HPV, compared to 9.5% of the keratinizing squamous cell cancer cases (p < 0.001). The most commonly detected HPV strain was type 16, followed by 31 and 33.
Infection with HPV type 16 appears to be strongly correlated to the development of warty or basaloid squamous cell cancer. Vaccination against HPV can be expected to prevent this type of vulvar cancer.