chondrom

Chondroma is a benign cartilaginous tumor composed of mature hyaline cartilage. It most commonly occurs in bone (intraosseous) as enchondromas, but can also arise on the bone surface as periosteal chondromas or in soft tissues as soft tissue chondromas. Enchondromas are the typical intramedullary lesions of small bones of the hands and feet, though they may be found in other bones as well.

Clinically, chondromas are often asymptomatic and discovered incidentally. When symptomatic, they may cause swelling, bone pain, or pathologic fractures, particularly in long bones. Imaging typically shows a well-defined, lobulated lesion within the bone or on the bone surface with chondroid calcifications. On radiographs, ring-and-arc calcifications may be seen, with thinning or expansion of the cortex. MRI and CT can help delineate extent and assess for features suggestive of malignancy.

Treatment depends on location, symptoms, and suspicion of malignant change. Asymptomatic enchondromas in noncritical locations may be observed. Symptomatic lesions or those at risk of fracture are commonly treated with curettage and filling of the defect, sometimes with bone grafting. Periosteal or soft tissue chondromas are often managed with local excision. In aggressive lesions, recurrent disease, or when malignant transformation is suspected, wider resection and oncologic assessment are indicated.

Prognosis is generally good after complete removal, but recurrence can occur, especially for incompletely excised lesions. Malignant transformation to chondrosarcoma is rare but is more likely in the setting of multiple enchondromas, as seen in Ollier disease or Maffucci syndrome. Diagnosis relies on clinical, radiographic, and histologic correlation.