The cause of most bone cancers isn’t known. Bone cancer starts when cells in or near a bone develop changes in their DNA. A cell’s DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.
The cancer cells might form a mass called a tumor. The tumor can grow to invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it’s called metastatic cancer.
Risk Factors
Things that increase the risk of bone cancer include:
- Inherited genetic syndromes.Certain rare genetic syndromes passed through families increase the risk of bone cancer. Examples include Li-Fraumeni syndrome and hereditary retinoblastoma.
- Other bone conditions.Some other bone conditions may increase the risk of bone cancer. The other bone conditions include Paget’s disease of bone and fibrous dysplasia.
Diagnosis
Bone cancer diagnosis often involves imaging tests to look at the affected bone. To be certain whether a growth in the bones is cancer, a piece of tissue might be removed and tested for cancer cells.
Imaging tests
Imaging tests make pictures of the body. They can show the location and size of a bone cancer. Tests might include:
- X-ray.
- Magnetic resonance imaging, also called MRI.
- Computerized tomography scan, also called CT scan.
- Positron emission tomography scan, also called PET scan.
- Bone scan.
Biopsy
A biopsy is a procedure to remove a sample of tissue for testing in a lab. For bone cancer, the sample of tissue might be collected by:
- Inserting a needle through the skin.During a needle biopsy, a healthcare professional inserts a thin needle through the skin and guides it into the cancer. The health professional uses the needle to collect small samples of tissue.
- Removing the sample during surgery.During a surgical biopsy, a surgeon makes an incision in the skin to access the cancer. The surgeon removes a piece of the cancer for testing.
Determining the type of biopsy you need and the details of how to do the biopsy requires careful planning by your medical team. Healthcare professionals need to perform the biopsy in a way that won’t interfere with future surgery to remove bone cancer. For this reason, ask for a referral to a healthcare team that treats a lot of bone cancers before your biopsy.
Stages of bone cancer
If you’re found to have bone cancer, often the next step is to find out the extent of the cancer. This is called the cancer’s stage. Your healthcare team uses your cancer’s stage to help create your treatment plan. To determine the stage of the cancer, the healthcare team considers:
- The cancer’s location.
- The size of the cancer.
- How fast the cancer is growing.
- The number of bones affected, such as number of affected vertebrae in the spine.
- Whether the cancer has spread to the lymph nodes or to other parts of the body.
The stages of bone cancer range from 1 to 4. A stage 1 bone cancer generally is a small cancer that is growing slowly. As the cancer grows larger or grows more quickly, the stages get higher. A stage 4 bone cancer has spread to the lymph nodes or to other parts of the body.
Treatment
Bone cancer treatments include surgery, radiation and chemotherapy. Which treatments are best for your bone cancer will depend on several factors. These factors include the type, location and stage of the bone cancer. Your healthcare team also considers your overall health and your preferences.
Surgery
The goal of surgery for bone cancer is to remove all of the cancer. The surgeon may remove the bone cancer and some of the healthy tissue around it. Then the surgeon repairs the bone. This might involve using a piece of bone from another part of your body. Sometimes the bone is repaired with metal or plastic material.
Sometimes surgeons need to remove an arm or leg in order to get all of the cancer, though this isn’t common. It might be needed if the cancer grows very large or if the cancer is in a place that makes surgery difficult. After an arm or leg is removed, you may choose to use an artificial limb. With training and time with the new limb, you can learn to do everyday tasks.
Chemotherapy
Chemotherapy treats cancer with strong medicines. Many chemotherapy medicines exist. Most chemotherapy medicines are given through a vein. Some come in pill form.
Chemotherapy is often used after surgery for some types of bone cancers. It can kill any cancer cells that remain and lower the risk that the cancer will come back. Sometimes chemotherapy is given before surgery to shrink a bone cancer and make it easier to remove.
Not all types of bone cancers respond to chemotherapy treatments. Chemotherapy is often used to treat osteosarcoma and Ewing sarcoma. It’s not often used for chondrosarcoma.
Radiation therapy
Radiation therapy treats cancer with powerful energy beams. The energy can come from X-rays, protons or other sources. During radiation therapy, you lie on a table while a machine moves around you. The machine directs radiation to precise points on your body.
Radiation therapy might be used after surgery to kill any bone cancer cells that might remain. It also might help control bone cancer when surgery isn’t an option.
Some types of bone cancers are more likely to be helped by radiation therapy than others. Radiation therapy may be an option for treating Ewing sarcoma. It’s not often used to treat chondrosarcoma or osteosarcoma.