Assessment of Vulvar Intraepithelial Neoplasia (VIN) Grades Based on Dermoscopic Features: A Diagnostic Study

Introduction: Vulvar intraepithelial neoplasia (VIN) is a vulvar skin lesion considered a precursor of vulvar squamous cell carcinoma. No characteristics have been discovered to date that allows us to differentiate between grades of VIN, such as correlating the thickness of involvement of the epithelium (VIN1, VIN2, and VIN3) to the dermoscopic pattern. Objectives: The aim of this study was to correlate the clinical and dermoscopic features of VIN cases with histopathological findings, with the purpose of identifying dermoscopic characteristics that allow us to differentiate between different grades of VIN. Methods: A retrospective study of the clinical and dermoscopic characteristics of VINs was recruited. Clinical and dermoscopic characteristics, as well as histopathology data, were gathered from patients at two Dermatology Units in Italy during the period spanning from January 2020 to December 2021. Results: The study population consisted of 20 patients with a histologically confirmed diagnosis of VIN. The mean age of patients at the time of diagnosis was 55 years. At the dermoscopic level, VIN1 was characterized by a homogeneous erythematous area that completely involved the entire lesion, with a vascular pattern consisting of regular glomerular vessels. VIN3, was characterized by the presence of compact milky white areas that involved almost the entire lesion. VIN2 was characterized by the presence of non-compact white areas that allowed homogeneous erythematous areas to be seen transparently, without other distinguishing aspects. Conclusions: Although a definitive diagnosis and grading of VIN remains confirmed only histopathologically, our study shows how dermoscopy may aid the differential diagnosis between the different grades of VIN; the presence of a compact milky white area that involves nearly the entire lesion should be interpreted as an alarming feature, while homogeneous erythematous areas or a glomerular vascular pattern are more typical of the first stage of this neoplasia.