Tubulo-squamous vaginal polyp with basaloid epithelial differentiation.

Tubulo-squamous polyp is a recently described and apparently benign lesion that most frequently involves the upper vagina of postmenopausal patients. Histologically, it is characterized by the presence of cysts, squamous epithelial nests, and small tubular structures that are surrounded by a hypocellular fibrous stroma. Some lesions show focal immunoreactivity for prostatic acid phosphatise and/or prostate-specific antigen raising the possibility of derivation from Skene's glands. In this report, an additional case of tubulo-squamous polyp is presented in which there was prominent basaloid epithelial differentiation, mainly in the form of elongated cords of cells around the peripheral and deep aspect of the lesion. This feature has not been recorded previously in tubulo-squamous polyp and potentially could create diagnostic difficulty with other lesions such as basal cell/adenoid basal carcinoma or small-cell neuroendocrine carcinoma.