CLINICAL SUMMARY Lipoma is the most common soft tissue tumor and consists of benign adipose tissue. It is usually easy to identify on physical examination and on imaging studies. Subcutaneous…

Giant Cell–Containing Tumors Giant Cell Tumor, Chondroblastoma, Nonossifying Fibroma, and Chondromyxoid Fibroma SUMMARY All of these lesions contain giant cells. The distinction is often made by observing the background cells,…

CLINICAL SUMMARY Synovial chondromatosis is a benign synovial disorder resulting in the production of numerous small, intraarticular osteochondral bodies. Treatment, consisting of removal of the bodies and synovectomy, is usually…

Schwannoma (Neurilemmoma) and Neurofibroma CLINICAL SUMMARY Schwannomas and neurofibromas are slow-growing, benign nerve sheath tumors that arise either eccentrically from peripheral myelin-producing cells or centrally from intraneural support cells, respectively….

Malignant Fibrous Histiocytoma, High-Grade Pleomorphic Undifferentiated Sarcoma CLINICAL SUMMARY Undifferentiated sarcoma is the preferred term for the previously named malignant fibrous histiocytoma (MFH). This designation probably encompasses a common endpoint…

Diffuse Pigmented Villonodular Synovitis (PVNS) CLINICAL SUMMARY Diffuse PVNS is a benign, proliferative disorder of the synovium with a distinctive complex nodular appearance on MRI. It is most common in…

History Age, Pain AGE The patient’s age and clinical presentation are very helpful in predicting the diagnosis in musculoskeletal tumors and greatly aid in the interpretation of the imaging studies….

Extraabdominal Desmoid Tumor, Aggressive Fibromatosis CLINICAL SUMMARY Fibromatosis is a benign, locally aggressive tumor originating in an intermuscular location, with a highly infiltrative growth pattern and a propensity to recur…

Tenosynovial Pigmented Villonodular Synovitis (PVNS), Nodular PVNS CLINICAL SUMMARY Giant cell tumor of tendon sheath is a slow-growing tumor associated with mechanical pain, most commonly in the hands and feet….

Congenital Venous Malformation, Intramuscular Hemangioma, Low-Flow Vascular Malformation CLINICAL SUMMARY Congenital vascular malformations can be found in any organ. Intramuscular lesions, often described as intramuscular hemangiomas , are easily recognized…