Sclerosing polycystic adenosis of parotid gland: a unique report of two cases occurring in two sisters.

Sclerosing polycystic adenosis (SPA) of salivary glands is a tumorous lesion of salivary glands, with clinical presentation of a slow-growing mass characterized by a combination of histological features, some of which are reminiscent of mammary fibrocystic disease. SPA is mostly unifocal, but rarely may be multifocal and/or bilateral. Recurrences have been reported in up to 19% of cases. Although originally considered pseudoneoplastic, the occurrence of "dysplasia" and carcinoma in situ of ductal epithelium, and recent evidence of clonality suggest a possible neoplastic nature. Herein we describe, for the first time, two cases of SPA in two sisters (7 and 33 years old). The younger patient experienced multiple recurrences. This is the first report of familial occurrence of SPA, suggesting a possible genetic background.