Long Bone Enchondroma vs. Low-Grade Chondrosarcoma: Current Concepts Review

Context Differentiation of low-grade chondrosarcoma (CS) from enchondroma (EC) is a clinical, radiological and pathological challenge. Considering its effect on the choice of therapeutic approach, this paper discusses the distinguishing criteria of low-grade CS and EC. Evidence Acquisition Evidence of this article came from the result of more than 15500 surgeries of musculoskeletal tumors performed at our center during the previous 26 years, in addition to an inclusive literature review of related published articles. Results Pain is considered as the most distinguishing clinical criteria of low-grade CS from EC. Aggressive radiologic criteria including cortical destruction, cortical thickening, deep endosteal scalloping and periosteal reaction favor the presence of low-grade CS. Predominantly, intermediate signal on T1-weighted MRI, multilocular appearance on contrast-enhanced T1-weighted MRI, extensive gadolinium enhancement, and peri-tumoral edema could also favor low-grade CS. In addition, permeation of the bone marrow by cartilage and separation of cartilage lobules by fibrous bands could be regarded as the pathologic characteristics of low-grade CS. Conclusions Radiological evaluation is considered as the first line method in the distinction of low-grade CS and EC. In this regard, attention should be paid to the presence of aggressive radiological features.