Nonsquamous Lesions of the Vulvar Skin and Subcutaneous Tissue: A Review (Part 1)

Objectives This article aimed to review "nonsquamous lesions of the vulvar skin and subcutaneous tissue"clinically and pathologically, based on the fifth edition of the World Health Organization tumor classification. Materials and Methods A database search of PubMed and Google Scholar was performed between 1970 and 2021, using the search terms "vulva,""lower genital tract,"and "nonsquamous lesions."The search was limited to "humans,""gynecopathology,"and "dermatopathology."Full article texts were reviewed. Reference lists were screened for additional articles. We excluded articles written in the non-English language and abstracts. Results A list of 600 articles was identified. Another screening identified 68 articles for clinicopathological features of nonsquamous lesions of the vulvar skin and subcutaneous tissue. In the first part of this review, we cover 5 major groups of nonsquamous lesions of the vulvar skin and subcutaneous tissue including (1) glandular tumors and cysts, (2) adenocarcinomas of other types, (3) germ cell tumors of the vulva, (4) neuroendocrine neoplasia, and (5) hematolymphoid hyperplasia and neoplasia. The rest of the major topics including mesenchymal tumors of the lower genital tract, melanocytic lesions, and metastasis will be discussed in the second part of this review. Conclusions Clinicopathological features of nonsquamous lesions of the vulvar skin and subcutaneous tissue as categorized by the updated World Health Organization classification are presented.