Alveolar soft part sarcoma.

This article provides an overview of the pathology of alveolar soft part sarcoma, focused on its morphology, special stains useful in diagnosis, and the clinical and radiographic features of the disease. Alveolar soft part sarcoma is a rare neoplasm of unknown histogenesis with poor prognosis. Although there are several immunohistochemical stains available to help reach the diagnosis, the morphology of the tumor should be considered the main diagnostic feature. The periodic acid-Schiff stain is the best single stain that supports the diagnosis.