[Vulvar intraepithelial neoplasia and vulvar cancer]

Vulvar intraepithelial neoplasia (VIN) is divided into human papillomavirus (HPV)-associated lesions (undifferentiated VIN, high-grade squamous intraepithelial lesion) and HPV-independent VIN (predominantly differentiated VIN). This new WHO classification is essential for the diagnostics, treatment and prognosis. While 90% of cases seen in practice are high-grade intraepithelial lesions (HSIL), dVIN cases are less common (10%), more difficult to diagnose and carry a higher risk of progression to cancer. The lichen sclerosus that most often underlies these lesions is responsible for these characteristics. The distinction between the two lesions is made using p53 and p16 immunohistochemistry on biopsy/excision specimens. Analogous to VIN, invasive carcinomas are also divided into HPV-associated and HPV-independent tumors. Here too, HPV-independent changes are associated with a worse prognosis. The treatment of dVIN is surgical, while treatment of uVIN can be ablative, surgical or medicinal (imiquimod being preferred). The recurrence rate is high regardless of the treatment chosen. Lifelong follow-up is therefore essential. In the case of an invasive carcinoma the majority of patients can be curatively treated with surgery alone. In cases of lymphatic metastasis, adjuvant chemo(radio)therapy is generally administered; in very advanced disease, particularly when continence function is threatened, primary chemoradiotherapy can also be used. Primary prevention of HPV-induced lesions is highly effective through primary HPV vaccination. Secondary prevention of dVIN/HPV-independent invasive carcinoma appears to be achievable through consistent maintenance therapy of the underlying lichen sclerosus with highly potent topical corticosteroids.