What is bone cancer?
Malignant tumors can grow almost anywhere in the body. When cells in your bone tissue degenerate and multiply uncontrollably, bone cancer develops. Medicine distinguishes between so-called primary bone tumors, which originate from bone tissue, and secondary tumors, which form as secondary tumors of another tumor disease, for example when breast cancer, lung cancer, prostate or thyroid cancer spread to the bone.
Bone cancer first makes itself felt through pain in the affected part of the skeleton. They often occur irregularly and intensify when you put weight on the bone. If the tumor continues to grow, it causes a visible swelling that hurts when touched. In some cases, the bone becomes brittle and fractures occur. If a bone sarcoma is detected and treated early, you have a good chance of being cured.
Bone sarcomas: causes and risk factors
There are three forms of bone cancer:
- Osteosarcoma is the most common bone tumor, with two to three new cases per million inhabitants per year.
- Chondrosarcomas are the second most common.
- Ewing sarcomas are very rare with 0.6 new cases per 1 million inhabitants per year.
Chondrosarcomas occur mainly in adults. Osteosarcomas and Ewing’s sarcomas affect people in childhood and adolescence – this is when the bone grows the most.
Osteosarcoma
Osteosarcoma (Greek osteon = bone) is the most common primary malignant tumor in the skeleton. It is a rare type of cancer; in Switzerland, around 10 to 15 people are diagnosed with it every year. Most illnesses occur in the age group between ten and 25 years. Boys and men are slightly more frequently affected than girls and women. Another group of patients falls ill around the age of 60.
The causes of osteosarcoma are largely unknown.
If you develop osteosarcoma, malignant tumor cells grow in the bone, forming immature, rapidly proliferating bone tissue. Tumors develop that displace and destroy healthy bone tissue. The malignant tumors mainly develop in the long tubular bones of the thigh, upper arm and tibia near the joints. About half of osteosarcomas form in the knee and about a tenth in the shoulder joint.
Chondrosarcoma
Chondrosarcoma (Greek chondron = cartilage) typically develops in the pelvis, trunk or in the long tubular bones close to the trunk. The tumor cells multiply uncontrollably, forming cartilage but, in contrast to osteosarcoma, no bone substance. The proliferating cartilage gradually displaces the healthy bone. The risk of developing the disease increases with age and peaks around the sixth decade of life. Chondrosarcoma responds very poorly to chemotherapy and radiotherapy. Treatment therefore consists primarily of surgical removal of the tumor.
Ewing’s sarcoma
Ewing’s sarcoma also predominantly affects children and adolescents. It is the second most common bone cancer affecting young people. The disease mainly affects male adolescents between the ages of twelve and 17. In principle, the sarcoma can form on any bone, but predominantly on the pelvis and femur.
The cause of Ewing’s sarcoma has not yet been clarified. There are no known hereditary or external influences that increase the risk of the disease. However, a typical, but not hereditary, chromosomal alteration is found in the tumor cells. Their detection enables the disease to be diagnosed.
Ewing sarcomas grow preferentially, but not exclusively, in bone tissue. Very rarely, they develop in soft tissue (connective, fatty or muscle tissue or tissue of peripheral nerves) – either with or without involvement of bone tissue.
This form of bone cancer often manifests itself through pain and is highly malignant. If it is treated consistently with chemotherapy, surgery to radically remove the tumor and radiotherapy, the patient’s chances of survival increase to around 70 percent.
Symptoms: They are often unspecific
Bone cancer does not manifest itself through characteristic symptoms, which is why it is often recognized late. Those affected complain of pain that increases and decreases depending on the strain, but persists at night. They often occur initially in connection with an injury. This is why they are often initially classified as sports injuries, bone inflammation or – in children and adolescents – as growing pains. However, while growing pains usually only occur at night, the symptoms of malignant bone tumors increase steadily and also persist during the day. In addition, there is swelling and redness in the affected area, which those affected often misinterpret as a bruise or inflammation.
The non-specific indications of the bone tumor make early diagnosis difficult. This is fatal, becausethe earlier a bone tumor is diagnosed and treated, the better the prognosis. How bone cancer progresses and whether the patient recovers depends primarily on the type of tumor and the stage of the disease.
Bone sarcomas: Diagnosis by us
If we suspect that you are suffering from a bone sarcoma, an X-ray is the diagnostic procedure of first choice. On the image, for example, we can see proliferating bone tissue (osteosarcoma), moth-eaten damage to the bone (Ewing’s sarcoma) or proliferating cartilage (chondrosarcoma).
Using other imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), skeletal scintigraphy or ultrasound, we can determine whether it is a benign tumor or actually a tumor.
We can then determine the type of tumor by means of a tissue examination (biopsy). We also look for metastases in your body to assess the stage of the cancer. Experts speak of “staging”.
Bone sarcoma: prevention, early detection, prognosis
The causes of bone sarcomas are largely unknown. That is why you cannot prevent it.
As bone sarcomas cause unspecific symptoms, early detection is difficult. Those affected should have bone pain, especially in the knee joint, checked by a doctor after four weeks at the latest by means of an X-ray.
The prognosis depends on the type of bone sarcoma you have and how early treatment is started. A malignant bone tumor is always a dangerous disease that will kill those affected within a few years without effective treatment.
Self-help groups
The exchange with people who are affected by the same disease can be a great support in coping with the disease. Advice on finding a suitable self-help group is available from
Selbsthilfe Zürich. Self-Help Zurich and the University Hospital Zurich are cooperation partners in the national project “Health literacy thanks to self-help-friendly hospitals”.
Bone sarcoma: Treatment depends on the type of tumor
The treatment of malignant bone tumors is a case for highly specialized medicine. It should be carried out at our clinic, which specializes in bone sarcomas. The treatment steps depend on the type and spread of the bone sarcoma. We usually follow standardized protocols and rely on a combination of several treatment options: Surgery, chemotherapy and radiotherapy should completely eliminate the bone tumor. There is a separate protocol for each type of bone sarcoma, which specifies the treatment steps that are most effective against this sarcoma according to current medical knowledge.
If we have to remove large parts of the bone during the operation, we use biological reconstructions or implants instead. Prostheses that grow with the child are available for children and adolescents.