Sclerosing polycystic adenosis: A case report with review of the literature.

Sclerosing polycystic adenosis (SPA) is primarily a disease of major salivary glands. It was recognized as a distinct morphologic entity by Smith et al. in 1996. To best of our knowledge, 67 cases of SPA are reported in English literature. Here, we describe a case of SPA showing classic histomorphological features, involving the parotid gland of a 17-year-old girl. It was diagnosed as mucoepidermoid carcinoma at a peripheral hospital and was referred to our center. Histologically, it was well circumscribed and composed of lobules, separated by hyalinized stroma. Lobules showed adenosis, foci of acinic cell hyperplasia, and intraductal epithelial proliferation. Immunohistochemistry with p63 highlighted myoepithelial layer around every duct, acinus, and also in foci showing epithelial hyperplasia. There was no evidence of malignancy. Awareness of SPA, a benign rare entity, is essential to avoid misdiagnosing it as other common salivary gland tumors which it may mimic.