{"entity":{"id":"chondrosarcoma","kind":"cancer","name":"Chondrosarcoma","aka":["Cartilage sarcoma","Atypical cartilaginous tumour (grade 1, limbs)","Dedifferentiated chondrosarcoma","Mesenchymal chondrosarcoma"],"tldr":"Chondrosarcoma is a cancer of cartilage-forming cells in bone. It is nearly immune to chemotherapy and radiotherapy, so complete surgery is the treatment, with proton or carbon-ion beams for skull base and spine tumours that cannot be fully removed. Half of conventional tumours carry an IDH mutation, and the IDH1 blocker ivosidenib is in a phase 3 trial.","summary":"Chondrosarcoma arises in bone from cartilage-producing cells and is graded 1 to 3; grade 1 tumours of the limbs were renamed atypical cartilaginous tumours in 2013 because they almost never metastasise, while grade 3 and dedifferentiated tumours spread early to the lungs. About half of conventional and most dedifferentiated tumours carry a mutation in IDH1 or IDH2, the same enzymes mutated in glioma and acute myeloid leukaemia, and mesenchymal chondrosarcoma carries a HEY1-NCOA2 fusion. The tumour's low cell turnover, poor blood supply and abundant cartilage matrix make it resistant to conventional chemotherapy and to standard-dose radiotherapy.\n\nSurgery is the only established curative treatment: curettage for atypical cartilaginous tumours of the limbs, wide resection for higher grades and for all pelvic and axial tumours, with limb-salvage reconstruction where feasible. Skull base and spinal tumours that cannot be resected completely are treated with high-dose proton or carbon-ion radiotherapy, which achieves local control in most cases. Dedifferentiated chondrosarcoma is treated like osteosarcoma with doxorubicin and cisplatin-based chemotherapy despite uncertain benefit, and mesenchymal chondrosarcoma with Ewing-type regimens.\n\nThe 2011 discovery of IDH mutations made chondrosarcoma a targetable disease. In the phase 1 study of ivosidenib in IDH1-mutant chondrosarcoma, most patients had stable disease as their best response with durable control in some, and the placebo-controlled phase 3 CHONQUER trial (NCT06127407) in conventional chondrosarcoma is now recruiting. Immunotherapy has shown occasional responses in dedifferentiated tumours, and there is no approved systemic therapy for any form.","asOf":"2026-09-17","wikipedia":"https://en.wikipedia.org/wiki/Chondrosarcoma","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Chondrosarcoma"}],"tags":["subtype-page"],"related":["osteosarcoma","chordoma"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"sarcoma","burden":"The commonest primary bone sarcoma of adults, typically diagnosed between 40 and 70 in the pelvis, proximal femur, shoulder girdle and ribs; low-grade tumours are cured by surgery alone, while dedifferentiated tumours are among the most lethal of all sarcomas.","subtypes":["Conventional central chondrosarcoma, grades 1 to 3 (IDH1/IDH2-mutant in about half)","Atypical cartilaginous tumour (grade 1 of the limbs; curettage)","Peripheral (secondary) chondrosarcoma arising in osteochondroma","Dedifferentiated chondrosarcoma (high-grade component; treated like osteosarcoma)","Mesenchymal chondrosarcoma (HEY1-NCOA2; Ewing-type chemotherapy)","Clear cell chondrosarcoma (epiphyseal, low grade)","Skull base and spinal chondrosarcoma (particle therapy)"],"biomarkers":["IDH1 or IDH2 mutation (ivosidenib eligibility)","Histological grade 1 to 3 and dedifferentiation","HEY1-NCOA2 fusion (mesenchymal)","COL2A1 mutations","Site (limb versus pelvis and axial skeleton)"],"standardOfCare":[{"setting":"Atypical cartilaginous tumour of the limbs","approach":"Intralesional curettage with local adjuvant, or observation of asymptomatic lesions; no chemotherapy or radiotherapy.","refs":["limb-salvage-surgery","active-surveillance","mri"]},{"setting":"Conventional grade 2 to 3, resectable","approach":"Wide en bloc resection with limb-salvage or pelvic reconstruction in a bone sarcoma centre; radiotherapy only for positive margins.","refs":["limb-salvage-surgery","imrt-igrt"]},{"setting":"Skull base and spine, incompletely resectable","approach":"Maximal safe surgery followed by high-dose proton or carbon-ion radiotherapy.","refs":["proton-therapy","carbon-ion","imrt-igrt"]},{"setting":"Dedifferentiated and mesenchymal","approach":"Surgery plus osteosarcoma-type (doxorubicin, cisplatin) or Ewing-type (doxorubicin, ifosfamide) chemotherapy, benefit uncertain.","refs":["doxorubicin","cisplatin","ifosfamide"]},{"setting":"Advanced IDH1-mutant conventional","approach":"Ivosidenib within the CHONQUER phase 3 trial or compassionate access; no approved systemic therapy.","refs":["ivosidenib","nct06127407","idh-inhibitors"]}],"stateOfArt":["Particle therapy gives durable local control of skull base chondrosarcoma that surgery alone cannot achieve.","IDH1 inhibition with ivosidenib produced durable stable disease in the phase 1 study and is being tested against placebo in the CHONQUER phase 3 trial.","Grading by an expert bone pathologist, not imaging alone, decides between curettage and wide resection."],"history":[{"year":1943,"title":"Lichtenstein and Jaffe separate chondrosarcoma from osteosarcoma","refs":[]},{"year":2011,"title":"IDH1 and IDH2 mutations found in chondrosarcoma and enchondroma","refs":["idh"]},{"year":2013,"title":"WHO renames grade 1 limb tumours atypical cartilaginous tumours","refs":[]},{"year":2020,"title":"Phase 1 ivosidenib in IDH1-mutant chondrosarcoma reports durable stable disease","refs":["ivosidenib"]},{"year":2023,"title":"CHONQUER phase 3 trial of ivosidenib opens","refs":["nct06127407"]}],"pipeline":["ivosidenib","nct06127407","idh-inhibitors","carbon-ion"],"openProblems":["No systemic therapy has ever been proven to help.","Dedifferentiated chondrosarcoma kills most patients within two years.","Distinguishing enchondroma from grade 1 chondrosarcoma remains unreliable."],"parent":"sarcoma"},"route":"/cancers/chondrosarcoma/","neighbours":{"cancer":[{"id":"chordoma","kind":"cancer","name":"Chordoma","route":"/cancers/chordoma/"},{"id":"osteosarcoma","kind":"cancer","name":"Osteosarcoma","route":"/cancers/osteosarcoma/"},{"id":"sarcoma","kind":"cancer","name":"Sarcomas (soft tissue, bone, GIST)","route":"/cancers/sarcoma/"}],"target":[{"id":"idh","kind":"target","name":"IDH1 / IDH2","route":"/targets/idh/"}],"drug":[{"id":"cisplatin","kind":"drug","name":"Cisplatin","route":"/drugs/cisplatin/"},{"id":"doxorubicin","kind":"drug","name":"Doxorubicin","route":"/drugs/doxorubicin/"},{"id":"ifosfamide","kind":"drug","name":"Ifosfamide","route":"/drugs/ifosfamide/"},{"id":"ivosidenib","kind":"drug","name":"Ivosidenib","route":"/drugs/ivosidenib/"}],"trial":[{"id":"nct06127407","kind":"trial","name":"Ivosidenib in Participants With Locally Advanced or Metastatic Conventional Chondrosarcoma Untreated or Previously Treated With 1 Systemic Treatment Regimen","route":"/trials/nct06127407/"}],"technology":[{"id":"active-surveillance","kind":"technology","name":"Active surveillance","route":"/technologies/active-surveillance/"},{"id":"carbon-ion","kind":"technology","name":"Carbon-ion therapy","route":"/technologies/carbon-ion/"},{"id":"idh-inhibitors","kind":"technology","name":"IDH inhibitors","route":"/technologies/idh-inhibitors/"},{"id":"imrt-igrt","kind":"technology","name":"IMRT / IGRT (modern external beam)","route":"/technologies/imrt-igrt/"},{"id":"limb-salvage-surgery","kind":"technology","name":"Limb-salvage surgery and endoprosthetic reconstruction","route":"/technologies/limb-salvage-surgery/"},{"id":"mri","kind":"technology","name":"MRI","route":"/technologies/mri/"},{"id":"proton-therapy","kind":"technology","name":"Proton therapy","route":"/technologies/proton-therapy/"}]}}