Orthopaedics
Since direct screening for bone cancer is not possible, maintaining regular check-ups for other types of cancer is crucial, explains Dr André Olivier, an orthopaedic oncology and joint reconstruction surgeon at Mediclinic Vergelegen.
Bone cancer occurs when cells within a bone start to grow in an uncontrolled fashion, forming tumours that are most often malignant, although they can be benign, according to the Cancer Association of South Africa (CANSA).
“But even a benign tumour can be invasive and grow aggressively, potentially leading to bone fractures and increased morbidity,” Dr Olivier says.
Only 1% of cancers around the world are caused by primary bone cancers (they originate within the bone), according to the American Cancer Association. More often, the tumour has a different site of origin, such as the breast or prostrate, and has spread to the bones as it has grown.
A multidisciplinary approach
Dr Olivier explains that orthopaedic surgeons work as part of a team to treat patients with tumours. “Our patients are usually referred to us by other specialists who have detected the first cancer,” he says.
The orthopaedic surgeon collaborates with a team of specialists, including an oncologist, radiologist, pathologist, and sometimes a gynaecologist or urologist, depending on the type of cancer. Together, they decide on the best treatment. Dr Olivier says this often involves removing the tumour, but the team aims to save the limb and avoid amputation whenever possible.
Secondary bone cancer is much more common than primary bone cancer and is usually found after the first cancer is diagnosed. For example, breast cancer may have been detected through a mammogram, and prostate cancer via a prostate-specific antigen (PSA) test.
Symptoms of bone cancer
When bone cancer starts in the bone, patients usually see their GP because they’ve noticed a lump or swelling in a limb. Swelling and pain at night are other common symptoms. Dr Olivier explains that night pain is a key sign: “Pain from an injury usually goes away over time. In the case of a tumour inside the bone, the pain remains consistent, alerting us that there is something more sinister at play,” he says.
It’s important to take note when a patient is seeing a physiotherapist but isn’t getting any relief. This type of pain often gets worse as the tumour grows and presses on surrounding areas. Loss of movement or function in a limb should also be checked to rule out other conditions like gout or arthritis.
How bone cancer is diagnosed
The first step in diagnosing the problem is usually an X-ray. However, the doctor may also order an MRI to look for issues in the muscles, nerves, tendons, and bones, as the results of X-rays can sometimes be limited. An ultrasound might also be recommended.
Dr Olivier explains that while scans can sometimes provide a diagnosis, a biopsy may still be needed. If the tumour is near the skin's surface, an ultrasound might be enough to confirm the diagnosis. However, if the tumour is deeper, a biopsy under general anaesthesia may be required.
He emphasises that if surgery is needed to remove the tumour, every effort is made to help the patient keep their limb. “The removal of a tumour from soft tissue is relatively simple, but if it is invasive, it becomes a more complex procedure,” he says. In this case, once the tumour is removed, the joint or part of the bone will be removed and replaced with an implant.
The implants used today are custom-made, modular structures. However, if the tumour is removed from a hard-to-reach area like the pelvis, a 3D-printed bone may be used instead.
Cancer screenings are key
Dr Olivier says that because bone cancer can't be screened for directly, it’s important to keep up with screens for other types of cancer. Finding cancer early can improve treatment outcomes and may help prevent it from spreading to other parts of the body, like the bones.