Osteosarcoma is the most common type of cancer that develops in bone. Like the osteoblasts in normal bone, the cells that form this cancer makebone matrix. But the bone matrix of an osteosarcoma is not as strong asthat of normal bones.

Most osteosarcomas occur in children and young adults. Teens are the most commonly affected age group, but osteosarcoma can occur at any age.

In children and young adults, osteosarcoma usually develops in areaswhere the bone is growing quickly, such as near the ends of the longbones. Most tumors develop in the bones around the knee, either in thedistal femur (the lower part of the thigh bone) or the proximal tibia (theupper part of the shinbone). The proximal humerus (the part of the upperarm bone close to the shoulder) is the next most common site. However,osteosarcoma can develop in any bone, including the bones of the pelvis(hips), shoulder, and jaw. This is especially true in older adults

Subtypes of osteosarcoma

Several subtypes of osteosarcoma can be identified by how they look on xraysand under the microscope. Some of these subtypes have a betterprognosis (outlook) than others.Based on how they look under the microscope, osteosarcomas can beclassified as high grade, intermediate grade, or low grade. The grade ofthe tumor tells doctors how likely it is that the cancer will grow and spreadto other parts of the body. The subtype is determined by a good biopsy and microscopic examination by an experienced pathologist. 

Stages of Osteosarcoma

Doctors further divide localized osteosarcomas into 2 groups:

  • Resectable cancers are those in which all of the visible tumor can be removed by surgery.
  • Non-resectable (or unresectable) osteosarcomas can’t be removed completely by surgery.

This staging is done with the help of CT scans of the chest, bone scan or PET CT scans.

Making treatment decisions

Once osteosarcoma is found and staged, the cancer care team will talk with you about treatment options. It’s important to be sure you understand your options. Ask your cancer care team questions. You can find some good questions to ask in the section What Should You Ask the Doctor About Osteosarcoma?

Because osteosarcoma is rare, only doctors in major cancer centers have a lot of experience treating these cancers.

For children and teens, a team approach is recommended that includes the child’s pediatrician as well as children’s cancer specialists. Treatment is best done at a children’s cancer center. For adults with osteosarcoma, the treatment team typically includes the patient’s primary care doctor, as well as specialists at a major cancer center. Doctors on the treatment team might include:

  • An orthopedic surgeon (a surgeon who specializes in muscles and bones) who is experienced in treating bone tumors
  • A medical or pediatric oncologist (a doctor trained to treat cancer with chemotherapy and other drugs)
  • A radiation oncologist (a doctor trained to treat cancer with radiation therapy)
  • A pathologist (a doctor specializing in lab tests to diagnose and classify diseases)
  • A physiatrist (a doctor specializing in rehabilitation and physical therapy)

For both adults and children, the team will also include other doctors, physician assistants, nurse practitioners, nurses, psychologists, social workers, rehabilitation specialists, and other health professionals. For more information.

The types of treatment used for osteosarcomas include:

  • Surgery
  • Chemotherapy
  • Radiation therapy (in certain cases)

Most often, both chemotherapy and surgery are needed.

All of these treatments may have side effects, but many of them can be made less troublesome. Your medical team will help you take care of the side effects and can help you work closely with nutritionists, psychologists, social workers, and other professionals to understand and deal with medical problems, stress, and other issues related to the treatment.

Because many of these issues can be more complex for cancer in children and teens, many people will be involved in your child’s overall care. As a parent, taking care of a child with cancer can be a very big job. It’s important to remember that you will have a lot of help. It’s also important for you to know that the health professionals who treat children with osteosarcoma are using the experience and knowledge gained from many decades of studying the treatment of this disease.