ENCHONDROMA VERSUS CHONDROSARCOMA IN THE APPENDICULAR SKELETON - DIFFERENTIATING FEATURES

Distinction of enchondroma versus intramedullary chondrosarcoma affect ing the appendicular skeleton (proximal to the metacarpals and metatar sals) is a frequent diagnostic dilemma, The authors studied a large se ries of patients with these lesions (92 with enchondromas, 95 with cho ndrosarcomas) using statistical assessment of both clinical parameters and numerous radiologic manifestations on images from multiple modali ties to identify differentiating features. Multiple clinical and imagi ng parameters demonstrated statistically significant differences betwe en enchondroma and chondrosarcoma, particularly pain related to the le sion, deep endosteal scalloping (greater than two-thirds of cortical t hickness), cortical destruction and soft-tissue mass (at computed tomo graphy or magnetic resonance imaging), periosteal reaction (at radiogr aphy), and marked uptake of radionuclide (greater than the anterior il iac crest) at bone scintigraphy, All of these features strongly sugges ted the diagnosis of chondrosarcoma, These criteria allow distinction of appendicular enchondroma and chondrosarcoma in at least 90% of case s.