- Terminology: “giant cell variant” (1927) → epiphyseal chondromatous giant cell tumor → calcifying giant cell tumor → chondroblastoma
- 1% to 2% of all primary bone tumors
- 9% of all benign bone tumors
- Mean age of 15-18 years
- M >>F
- Mean duration of symptoms 8.7 months
- Trivia: Most common benign neoplasm of the patella
- Epiphysis/apophysis +/- metaphyseal/diaphyseal involvement
- Metaphyseal/diaphyseal occurrence without epiphyseal/apophyseal involvement exceptionally rare
- Proximal tibia >> proximal femur > distal femur > proximal humerus
- Well-defined, sclerotic margins on radiographs
- Can involve the cortex, resulting in expansion, thinning, or disruption.
- Stippled matrix calcification seen in minority of cases
- Periosteal reaction seen in majority of cases
- Extensive peri-lesional edema on MRI is common
- Homogeneously hypointense on T1
- Variable on T2: can be diffusely hypointense, or have small cystic areas of increased T2 signal or fluid-fluid levels
- Heterogeneous and moderate enhancement in solid portions. Less commonly, homogeneous and marked enhancement
- Clear cell chondrosarcoma: Typically older patients
- Osteoid osteoma: Usually has intense perilesional sclerosis and edema.
- Langerhans cell histiocytosis:
- Chondromyxoid fibroma: Rare lesion. Usually in the metaphyses of the long tubular bones, especially the tibia and femur near the knee joint. May cross open growth plates into epiphyses or apophyses.
- Curettage or resection
- RFA (small lesions, small series, not common)
- Local recurrence rate: 5.0% after curettage
- Local recurrence rate: 0% after resection
- Recurrence most frequent in the proximal humerus
- Malignant transformation and benign pulmonary metastases extremely rare
- Christie-Large M, Evans N, Davies AM, James SL. Radiofrequency ablation of chondroblastoma: procedure technique, clinical and MR imaging follow up of four cases. Skeletal Radiol. 2008 Nov;37(11):1011-7.
- Kaim AH, Hügli R, Bonél HM, Jundt G. Chondroblastoma and clear cell chondrosarcoma: radiological and MRI characteristics with histopathological correlation. Skeletal Radiol. 2002 Feb;31(2):88-95.
- Singh J, James SL, Kroon HM, Woertler K, Anderson SE, Jundt G, Davies AM. Tumour and tumour-like lesions of the patella--a multicentre experience. Eur Radiol. 2009 Mar;19(3):701-12.
- Xu H, Nugent D, Monforte HL, Binitie OT, Ding Y, Letson GD, Cheong D4, Niu X. Chondroblastoma of bone in the extremities: a multicenter retrospective study. J Bone Joint Surg Am. 2015 Jun 3;97(11):925-31.