Giant cell tumor of tendon sheath: spectrum of radiologic findings.

Giant cell tumor of tendon sheath is the second most common tumor of the hand. It can also occur in larger joints. Radiologic features include a soft-tissue mass with or without osseous erosion. Less commonly, it can cause periostitis or permeative osseous invasion; it may rarely calcify. The entire imaging spectrum of this lesion is presented, with emphasis on atypical appearances which can mimic other lesions.