Bone Cancer in Children: Osteosarcoma and Ewing Sarcoma

Bone cancer in children is rare. The two most common types are osteosarcoma and Ewing sarcoma. Osteosarcoma usually starts in a long bone, often near the knee. Ewing sarcoma can start in many bones or in the soft tissue around a bone. Both are usually treated with chemotherapy plus surgery, radiation or both.

Osteosarcoma mostly affects teens and young adults. About 440 people age 19 and younger are diagnosed with it each year in the United States. More than half the time, it starts in a long bone near the knee. Ewing sarcoma also mostly affects teens and young adults, from the teen years into the mid-20s. It can start in a bone. It can also start in the soft tissue around a bone.

The most common signs are pain and swelling in a bone or joint. These signs may come and go at first. A limp, stiffness, or a fracture with no clear injury can also be a sign. Some children with Ewing sarcoma also get fever, fatigue, or weight loss they cannot explain. Any bone pain that keeps coming back is worth a doctor visit, especially in a growing child.

Doctors start with imaging tests. An X-ray comes first. A CT scan or MRI usually follows, to see the tumor in more detail. A biopsy is the step that confirms cancer. A small piece of the tumor is removed and checked under a microscope. This step matters a lot. The biopsy should be done by a surgeon who is an expert in bone cancer. It is best if that surgeon also removes the tumor later. A poorly placed biopsy can make that later surgery harder.

Treatment usually starts with chemotherapy. Doctors give it before surgery, to shrink the tumor and kill cancer cells that imaging cannot see. Surgery follows, to remove the tumor completely. Many children can have limb-sparing surgery. This removes the cancer while keeping the arm or leg. Some children need amputation instead. That choice depends on the tumor's size and exact location. Studies show survival is the same whether the first surgery saves the limb or is an amputation. After surgery, children usually get more chemotherapy, to kill any cancer cells left behind.

Ewing sarcoma is also treated with chemotherapy first. This usually lasts several months, to shrink the tumor. Then comes local treatment: surgery, radiation, or sometimes both. The choice depends on where the tumor is, and how it responded to chemotherapy. More chemotherapy usually follows. The whole process can take six months to a year. If Ewing sarcoma comes back after treatment, doctors may use high-dose chemotherapy with a stem cell transplant.

Clinical trials are an option for children with osteosarcoma or Ewing sarcoma. Ask your child's team whether a trial is open for their specific cancer.

Recovery does not stop when treatment ends. Children who had surgery may need help from a rehabilitation specialist. Treatment can also cause late effects years later, such as fertility problems or a second cancer. Ask your child's team for a written survivorship plan that covers rehab and long-term checkups.

Treat a fever during chemotherapy as an emergency, not a message to leave. Phone the oncology team at once, day or night, if your child's temperature reaches 100.4°F (38°C) or higher or if they get shaking chills. Chemotherapy lowers blood counts, and CDC says a fever during chemotherapy is a medical emergency, and an infection during chemotherapy can be life-threatening. If you cannot reach the team in minutes, take your child to an emergency department and tell the staff straight away that they are on chemotherapy. Call 911 if breathing becomes hard.

Call the care team right away for sudden severe pain in the affected limb, or a bone that gives way or breaks after only a small knock.

• Is limb-sparing surgery possible? What will recovery and rehab look like?
• How many rounds of chemotherapy are planned, and what side effects should we expect?
• Is a clinical trial available?
• What will follow-up scans and appointments look like once treatment ends?

Bone cancers can come back, and regular monitoring catches this early.

• National Cancer Institute — Osteosarcoma and Undifferentiated Pleomorphic Sarcoma of Bone Treatment (PDQ).
• National Cancer Institute — Ewing Sarcoma Treatment (PDQ).
• National Cancer Institute — Infections in People with Cancer.
• CDC — Fever and Cancer Treatment.