Once you've made the determination that a long bone lesion is a chondroid tumor, age and location can help narrow your differential diagnosis.
Chondroblastoma and clear-cell chondrosarcoma are epiphyseal lesions that can be indistinguishable. While chondroblastomas tend to affect a younger age group than clear-cell chondrosarcomas, there is some overlap.
Chondromyxoid fibromas are rare metaphyseal lesions that may not have an obvious chondroid matrix on radiography. They most commonly occur in the proximal tibia.
Enchondromas and chondrosarcomas are diaphyseal lesions that have characteristic appearances at their extremes. However, there can be significant overlap, especially between enchondromas and low-grade chondrosarcomas.
Please note that these are rough guidelines: Tumors don't read this blog.
- Greenspan A, Jundt G, Remagen W. Cartilage (Chondrogenic) Lesions. In Differential Diagnosis of Orthopaedic Oncology, 2nd Edition. 2007 Lippincott Williams & Wilkins; pp 162-255.
- Kindblom LG. Bone Tumors: Epidemiology, Classification, Pathology. in Imaging of Bone Tumors and Tumor-Like Lesions. Davies AM, Sundaram M, and James SLJ (eds). Springer-Verlag Berlin Heidelberg (2009); pp 1-4.