PET, CT, and MR Imaging of Extra-articular Pigmented Villonodular SynovitisNguyen, Ba D., MDClinical Nuclear Medicine: June 2007 - Volume 32 - Issue 6 - p 493-495 doi: 10.1097/RLU.0b013e318054cdf8 Interesting Image Buy Abstract Author InformationAuthors Article MetricsMetrics Pigmented villonodular synovitis is also known as fibrohistiocytic tumor by the World Health Organization classification of bone and soft tissue tumors. Pigmented villonodular synovitis is the name used for intra-articular lesions while diffuse-type giant cell tumor and localized tenosynovial giant cell tumor correspond to the extraarticular soft tissue variants of these benign tumors. The large size of these lesions may mimic malignancy due to aggressive cross-sectional imaging features and false-positive F-18 FDG PET findings. A case of giant extra-articular pigmented villonodular synovitis of the distal thigh with a brief review of its epidemiology and imaging characteristics is presented. From the Department of Radiology, Mayo Clinic, Scottsdale, Arizona. Received for publication October 17, 2006; accepted February 26, 2007. Reprints: Ba D. Nguyen, MD, Department of Radiology, Mayo Clinic, 13400 E. Shea Blvd., Scottsdale, AZ 85259. E-mail: firstname.lastname@example.org. © 2007 Lippincott Williams & Wilkins, Inc.