patient friendly version of consensus on key issues
This consensus was developed by 314 delegates from 59 countries who participated in a two-day consensus meeting in Cape Town, South Africa. This publication can be found here.
When is scraping out the tumor (curettage) preferred, and when is removing the bone (resection) needed? Whenever possible, doctors try to preserve the joint by removing the tumor from inside the bone by scraping (called curettage) rather than removing part of the bone via resection. This approach usually helps patients maintain better movement and function long term.
Removing a larger section of bone (resection) is generally reserved for situations where the joint cannot be saved, the tumor is in a bone that can be removed without major functional loss, and the tumor has come back multiple times and can no longer be managed with curettage. Although curettage has a higher chance of the tumor returning, many recurrences can be successfully treated while still preserving the joint. What if the tumor has caused a fracture? For most patients whose GCTB has caused a broken bone, curettage remains the preferred treatment if the joint can be preserved.
Patients treated with curettage generally have better function, better quality of life, and acceptable recurrence rates More extensive surgery may be needed if: -The fracture extends into the joint -The fracture is very complex -The tumor has spread into nearby soft tissues
What is denosumab and when is it used? Denosumab is a medication that can reduce pain and other symptoms, shrink or stabilize the tumor, make surgery easier or less extensive, and help control disease that has spread to the lungs or is difficult to operate on. It is often considered when surgery would be especially difficult or could cause significant disability. It is also considered for GCTB that has spread to the lungs.
Does denosumab increase the chance of the tumor coming back? The answer depends on the type of surgery. For patients having curettage, denosumab use before surgery may increase the risk of the tumor returning.
For patients having a complete bone resection, denosumab may help surgeons remove the tumor completely and does not appear to increase recurrence because the entire bone segment is removed.
Rare cases of cancer developing from GCTB after denosumab have been reported, but a direct cause-and-effect relationship has not been proven.
How long should denosumab be used before surgery? If denosumab is used to prepare for surgery: -Short courses are preferred (typically a few weeks to several months, with an emphasis on less injections) -Treatment longer than six months is generally avoided before curettage due to increase risk of recurrence
There is currently no evidence that routinely continuing denosumab after surgery reduces recurrence or that it should be used preventatively.
Is long-term denosumab safe? Denosumab appears relatively safe for up to about two years. Potential long-term side effects include: -Osteonecrosis of the jaw (damage to the jaw bone) -Low calcium levels -Rare atypical fractures
Because risks increase with longer treatment, long-term use should be carefully monitored by an experienced medical team.
Can denosumab doses be spaced out or stopped? Some evidence suggests that patients with stable disease may be able to receive denosumab every 8–12 weeks instead of every 4 weeks. However, stopping treatment completely may allow the tumor to grow again and high calcium levels can sometimes occur after stopping. Any dose reduction or treatment break should be closely supervised.
Are additional treatments used during surgery? Yes. During curettage, surgeons often use techniques to reduce the risk of recurrence, including: -High-speed burrs to remove microscopic tumor cells -Bone cement (PMMA)
Bone cement has the strongest evidence for reducing recurrence. Bone cement should be used over cadaver when possible. Other treatments, such as argon beam or chemical agents, have less evidence supporting their benefit. Can zoledronic acid + bone cement help? Some studies suggest that adding medications such as zoledronic acid to bone cement may help control the tumor locally. However, evidence is still limited.
Does adding bone graft under the joint help? Yes. For tumors near a joint, placing a layer of bone graft between the cartilage and bone cement may lower the risk of future fractures and reduce the risk of arthritis. Importantly, it does not appear to increase recurrence.
How are lung metastases treated? When GCTB spreads to the lungs, many patients can initially be monitored with regular scans because the disease may remain stable and, rarely, it may even regress on its own.
Denosumab helps stabilize the disease and can help avoid surgery. Surgery on the lungs should be reserved for a small number of growing lung nodules or unresponsive nodules. What if the tumor comes back in soft tissue? Although there are few available studies to base this off of, but surgery is usually effective to remove the disease. In some cases, denosumab may be used before surgery to shrink the recurrence and make surgery easier if the bone segment is expected to be removed.
How is GCTB of the sacrum treated? The use of denosumab and arterial embolization (blocking blood flow to the tumor) has shifted treatment away from major surgeries when possible. Treatment with denosumab often focuses on preserving function, controlling the disease, and avoiding major surgery. This typically includes administering denosumab or arterial embolization (blocking blood flow to the tumor). Patients should discuss the benefits and long-term risks of treatment with their care team.
Is long-term denosumab an option for spine or sacral tumors? For patients with tumors that cannot be safely removed, long-term denosumab can provide durable disease control. Some patients may eventually be able to switch to dosing every 8–12 weeks while maintaining control, typically after 1-2 years after treatment.
When should chest scans be performed? Because GCTB can occasionally spread to the lungs, all patients should have chest imaging at diagnosis. More frequent chest scans may be recommended for patients with tumor recurrence, tumors in the spine or pelvis, younger age, and more aggressive tumors (Campanacci Grade III).
How often should patients be followed? The risk of metastatic disease is low. The risk of local recurrence is highest during the first few years after treatment. Most patients should have regular clinic visits, imaging of the affected bone, and chest imaging. Follow-up is usually most frequent during the first 2 years and gradually becomes less frequent over time. Additional scans may be needed if symptoms develop or if the tumor is in a high-risk location.
