Vulvar Ectopic Tissues, Cysts, and Benign Adnexal Tumors

The vulva represents the female external genitalia external to the hymen, extending anteriorly to the mons pubis, posteriorly to the anus, and laterally to the inguinal-gluteal folds. It contains various histological structures including hair follicles, sebaceous, sweat, anogenital mammary-like, vestibular, and periurethral glands, which can give rise to various benign adnexal tumors. This chapter addresses the recent literature and our personal experience on benign cystic lesions, ectopic tissues, lesions of major and minor vestibular glands, benign lesions of anogenital mammary-like glands, and benign adnexal tumors of the vulva. Discussed are the normal anatomy and histology of the vulva as well as the clinical presentation, histopathological and immunohistochemical features and the differential diagnosis of paraurethral and Bartholin’s gland cyst, mesonephric-like and mesothelial cyst, prostatic-type tissue of the vulva, endometriosis, hidradenoma papilliferum, fibroadenoma and benign phyllodes tumor, lactating adenoma, adenosis tumor, mammary-type fibrocystic disease and hamartoma, syringoma, cylindroma, spiradenoma, spiradenocylindroma, apocrine and eccrine mixed tumors and others.