Tophaceous pseudogout: A pitfall in the diagnosis of chondrosarcoma

Tumoral calcium pyrophosphate dihydrate deposition disease (TCPPD, tumoral or tophaceous pseudogout) is a rare nonneoplastic entity which mimics soft- tissue or skeletal malignancy. We present here the fine-needle aspiration c ytology findings of a unique case of TCPPD in a 76-yr-old woman, vith a lar ge paraischial soft-tissue mass diagnosed as a malignant neoplasm. The diff iculty in diagnosing such lesions by fine-needle aspirates is discussed and reviewed in the context of known cases from the literature. (C) 2001 Viley -Liss, Inc.