Giant Cell Tumour of Bone (GCT)
A benign but locally aggressive bone tumour, most often near the knee. With modern surgery and adjuvants, more than 90% of patients achieve long-term control with excellent function.
What is a Giant Cell Tumour of Bone?
Giant Cell Tumour of Bone (GCT) is a benign but locally aggressive bone tumour made up of multinucleated osteoclast-like giant cells and mononuclear stromal cells. It accounts for about 20% of all benign bone tumours and 5% of all primary bone tumours.8
Who gets GCT and where does it occur?
80% in the 3rd decade; rare before skeletal maturity
Slight female predominance
Distal femur & proximal tibia; then distal radius, hip, spine, sacrum
- • Eccentric, epiphyseal and expansile growth
- • Metaphyseal–epiphyseal junction involvement
- • Juxta-articular location near major joints
What causes GCT?
The exact cause is unknown. What we do know:
- • Extensive proliferation of osteoclast-like giant cells that destroy normal bone
- • RANK / RANKL pathway activation drives bone destruction
- • A self-perpetuating tumour–bone vicious cycle
can rarely metastasise to the lungs — but these are usually treatable and not fatal.12
What are the symptoms of GCT?
How is GCT diagnosed?
- • X-ray: eccentric lytic lesion in the metaphysis–epiphysis with variable bone destruction
- • MRI: T1 hypointense, T2 hyperintense; may show fluid-fluid levels (secondary ABC component)
- • CT: best for assessing cortical destruction
- • Chest CT: essential to detect pulmonary metastases
- • Image-guided core needle biopsy is mandatory
- • Pathognomonic abundance of multinucleated giant cells with stromal cells
- • Giant cells show high RANK receptor expression
Campanacci classification
Giant Cell Tumour — video playlist
A curated playlist of patient-friendly explainers and surgical discussions on giant cell tumour of bone.
Open playlist on YouTube →Current treatment options for GCT
Surgery is the cornerstone of treatment, with extended curettage now the gold-standard joint-preserving option. Adjuvants and modern medical therapy further reduce recurrence.1,3
Extended Curettage (Gold Standard)
- • Curettage with high-speed burr (1–2 mm extension)
- • Recurrence 4–8% (vs. 20–50% with simple curettage)
- • Excellent MSTS functional scores in modern series
- • Argon laser beam to burn cavity walls — excellent results
- • Traditional adjuvants: hydrogen peroxide, phenol, liquid nitrogen
- • Chemical cauterisation: 85% MSTS functional scores, 6% recurrence
Reconstruction Options
Auto- or allograft. More biological reconstruction with ~90% success, but slower healing and limb protection needed.
Immediate structural support and earlier recurrence detection. Cytotoxic heat effect extends 1.5–2 mm. Used in ~85% of cases.
Plates, screws or nails combined with grafts/cement — individualised by stage, location and joint proximity.
En-bloc Resection & Limb Salvage
- • Indications: Grade III with joint destruction or failed curettage
- • Reconstruction: tumour prosthesis, arthrodesis or biological reconstruction
- • Recurrence: lower (~8.3%) than extended curettage (~23%) in higher-risk lesions
- • Function: Good (MSTS ~78%) but lower than curettage (~94%)
Medical & Adjunct Therapies
- • Primary use: unresectable axial-skeleton GCT
- • Neoadjuvant: downstage large tumours before surgery
- • 86% response rate in phase 2 trials
- • Caution: may increase local recurrence; careful selection needed
- • Zoledronic acid 4 mg IV: peri-operative use can reduce local recurrence; helpful for lung metastases
- • Angio-embolisation: for large pelvic / sacral lesions or high surgical risk
Recurrence and metastases
What's the outlook with GCT?
The outlook for GCT is excellent. Modern techniques achieve >90% cure rates with strong return to activity (94% with extended curettage). Even in the rare cases with lung metastases, long-term survival is generally good.1,7
- • Pain (VAS) typically improves from 4.3 ± 1.2 to 2.1 ± 1.5
- • Function (MSTS) improves from ~59% to ~85%
- • Low rates of joint stiffness (~25%), infection (~9%), osteoarthritis (~6%)
Surveillance protocol
- • First 2 years: every 3 months — local X-ray + chest X-ray/CT
- • After 2 years: annual follow-up
- • Long-term surveillance for late recurrence
- • New or worsening pain at the surgical site
- • New swelling or loss of function
- • Respiratory symptoms (cough, breathlessness)
- • Any concerns about treatment progress
Which approach is best for me?
- • Grade II–III lesion with intact joint surface
- • Joint preservation is the priority
- • Accessible location for thorough curettage
- • Joint destruction or large soft-tissue mass
- • Failed previous curettage
- • High-risk site where recurrence would be catastrophic
- • Unresectable axial-skeleton lesion
- • Need to downstage before surgery
- • Surgery contraindicated, or pulmonary metastases
Talk to a specialist
References
- 1Journal of Medical Association of Thailand — Extended curettage vs. wide excision outcomes around the knee, 2012
- 2NCBI PMC — Denosumab treatment effects on blood supply and surgical planning, 2018
- 3NCBI PMC — Local recurrence analysis after curettage and cementing, 2011
- 4Clinics in Orthopedic Surgery — Local recurrence evaluation with denosumab treatment, 2019
- 5World Journal of Clinical Oncology — Comprehensive denosumab regimens systematic review, 2025
- 6NCBI PMC — Progress on denosumab use and dosing considerations, 2022
- 7Menoufia Medical Journal — Functional and oncological outcomes of extended curettage, 2024
- 8NCBI PMC — Comprehensive review of pathophysiology and treatment, 2023
- 9NCBI PMC — Metastatic GCT narrative review and management, 2022
- 10Frontiers in Oncology — Unresectable pulmonary metastases case report, 2023
- 11Pathology and Oncology Research — Management and surveillance of metastatic GCT, 2025
- 12NCBI PMC — Pulmonary metastasis comprehensive analysis, 2014
Important Notice: This information is provided for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. The content on this page should not be used to diagnose or treat any health condition.
Always seek the advice of a qualified orthopaedic oncologist or healthcare provider with any questions about giant cell tumour of bone or any other medical condition.
Treatment decisions are complex and must be individualised based on tumour size, location, Campanacci grade, age, functional needs, prior treatment, and patient preferences. Both extended curettage and en-bloc resection achieve excellent outcomes when appropriately selected and performed by experienced orthopaedic oncologists.
Denosumab therapy requires careful consideration of risks and benefits and should only be administered under the supervision of qualified specialists familiar with its use in bone tumours.
Long-term surveillance is essential for all GCT patients due to the potential for local recurrence and rare pulmonary metastases.
In case of emergency or urgent symptoms such as severe pain, suspected fracture, respiratory symptoms, neurological changes, or signs of infection, seek immediate medical attention or contact your local emergency services.
The Orthoncology Clinic is committed to providing current, evidence-based information while emphasising the importance of professional medical consultation for all health-related decisions.