Osteosarcoma: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Osteosarcoma?
A pediatric oncologist (a doctor who treats children with cancer) usually oversees care for osteosarcoma. An orthopedic surgeon (a bone and joint surgeon) who has experience treating bone tumors is also part of the team. Adults are usually cared for by an oncologist (a cancer doctor). A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is osteosarcoma?
Osteosarcoma is a rare type of bone cancer that starts in cells called osteoblasts, which form new bone. It is the most common type of bone cancer. Most cases happen in children, teens, and young adults.
Osteosarcoma usually forms in the long bones of the arms and legs. Over half of people with it have it in the long bones near the knee. It can start in any bone.
Symptoms
Symptoms depend on where the tumor is, how large it is, and whether it has spread.
- Bone or joint pain near the tumor, which is the most common symptom. At first the pain may come and go or be worse at night.
- A swelling or lump you can see or feel at the site of the tumor.
- A limp or trouble walking.
- A bone that breaks for no known reason.
If the cancer spreads to the lungs, it can cause cough, trouble breathing, and chest pain.
Causes and who gets it
Having past treatment with chemotherapy (cancer-killing drugs) or radiation can raise the risk of osteosarcoma. Certain conditions also raise the risk, such as Li-Fraumeni syndrome, Rothmund-Thomson syndrome, Werner syndrome, Bloom syndrome, Diamond-Blackfan anemia, and Paget disease. Not every child with a risk factor gets osteosarcoma, and some children with no known risk factor do.
Osteosarcoma most often spreads to the lungs. It may also spread to other bones.
How doctors diagnose it
Imaging tests such as an X-ray, CT scan, and MRI are done before a biopsy.
A biopsy takes a sample of tissue from the tumor so a pathologist can look at it under a microscope to check for cancer. The biopsy should be done by a surgeon who is an expert in treating bone cancer. After the diagnosis, imaging tests such as a bone scan or PET scan are used to find out whether the cancer has spread.
Treatment
Treatment for children should be planned by a team of health care providers who are experts in treating cancer in children. High-grade osteosarcoma, the most common type, needs to be treated with surgery and chemotherapy. Surgery to remove the entire tumor is done when possible. Chemotherapy before surgery can make the tumor smaller, so less bone tissue needs to be removed.
Limb-sparing surgery removes a tumor in an arm or leg without amputation (removing the limb). It is often an option for children with osteosarcoma in an arm or leg. Amputation removes part or all of an arm or leg and may be done when the whole tumor cannot be removed with limb-sparing surgery. Studies have shown that survival is the same whether the first surgery is limb-sparing surgery or amputation.
Osteosarcoma cells are not killed easily by external radiation therapy. Cancer treatment can cause side effects, and late effects can start 6 months or more after treatment. Late effects may include infertility, changes in mood, thinking, learning, or memory, and second cancers. Follow-up tests continue from time to time after treatment ends to show if the cancer has come back.
When to see a doctor
Check with your child's doctor if your child has swelling over a bone, bone or joint pain, a limp, joint stiffness, or a bone that breaks for no known reason. See a doctor if these symptoms do not go away within a few weeks or get worse. People with a fracture next to or through an osteosarcoma often describe a limb that was sore for a few months and suddenly became very painful. If this happens to your child, see a doctor. Call 911 or go to the emergency room if you have trouble breathing, or chest pain or discomfort lasting two minutes or more. These can be signs that the cancer has spread to the lungs.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. This doctor can examine a painful or swollen bone and refer you quickly to a cancer team if something looks wrong. After treatment, a primary care doctor can help keep follow-up visits organized.
Common questions
Is osteosarcoma common?
No, osteosarcoma is rare. In the United States, about 440 cases are diagnosed each year in people 19 years and younger.
Does osteosarcoma always mean losing a limb?
No, because limb-sparing surgery removes a tumor in an arm or leg without amputation. It is often an option for children with osteosarcoma in an arm or leg. If the surgeon cannot remove all of the tumor and enough healthy tissue around it, an amputation may be done.
Can osteosarcoma come back?
Yes, it can come back in the bone or in other parts of the body. When it returns, it is usually within 18 months after treatment is completed.
Is bone pain in a child usually cancer?
No, limb pain and swelling in active children and teens are much more likely to come from bumps and bruises from sports or other activities. Still, see a doctor if the symptoms do not go away within a few weeks or get worse.
Sources
- National Cancer Institute - Osteosarcoma and UPS of Bone Treatment (PDQ) Patient Version
- American Cancer Society - Osteosarcoma
- American Cancer Society - Signs and Symptoms of Osteosarcoma
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
