Histopathologic spectrum of vulvar lesions in South India with an emphasis on morphological classification of vulvar squamous cell carcinoma: a retrospective study of 8 years

Abstract

Background Vulvar diseases comprise inflammatory and neoplastic conditions. Comprehensive data in Indian population is lacking. Vulva is also prone to HPV related lesions and the prevalence of HPV related vulvar squamous cell carcinoma (SCC) in the study population is not known. Objectives The primary aim of this study was to describe the range of vulvar lesions over a period of 8 years in South Indian population. Additionally the vulvar squamous neoplasias were subclassified into morphological types in an attempt to differentiate the HPV and non HPV associated lesions, which helps in triaging cases for HPV testing. Methods The vulvar lesions from database were categorised as inflammatory, cysts, non-neoplastic proliferations and neoplasms. The inflammatory lesions were classified as lichenoid and acanthotic patterns. The squamous neoplasias were morphologically categorised into HPV and non HPV associated types. Results There were 204 biopsies from 192 adults and 10 children. Epithelial ones were commoner than mesenchymal (48 vs.18). Benign adnexal neoplasms included hidradenoma papilliferum, syringoma , apocrine adenoma. The commonest malignancy was squamous cell carcinoma (SCC) (n=21) of which 17 were classified as HPV associated and 4 non-HPV associated. SCC subtypes were warty (n=3), basaloid (n=5), mixed (n=1) and arising from differentiated VIN(n=8). One case of basal cell carcinoma was reported. There were 15 cases of VIN [5 LSIL and 10 HSIL {3 warty, 5 basaloid,2 mixed}], one extramammary Paget’s disease. Vascular neoplasms were the commonest mesenchymal lesions. There was one case each of leiomyosarcoma and angiosarcoma. Among non-neoplastic proliferations, fibroepithelial polyps were the commonest (n=9). Lichenoid inflammatory lesions (n=75) was more common than acanthotic (n=4). Conclusion The study highlights the importance of histopathologic typing of SCC and VIN, which helps in triaging cases for HPV testing in resource limited setting.