Sclerosing polycystic adenosis is a pseudoneoplastic inflammatory lesion which usually presents as a discrete mass in the parotid gland. It is composed of fibrohyaline stroma containing dilated ductal and acinar structures as shown here. It bears some resemblance to sclerosing adenosis and fibrocystic disease of the breast. Image courtesy of: Dr. Simon Chiosea, Associate Professor of Pathology, Univ. of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.