Also called osteogenic sarcoma, osteosarcoma is one of the most common types of bone cancer in children. The disease usually occurs in the long bones, such as the arms (humerus), legs (femur/tibia) and pelvis. It rarely occurs in the jaw and fingers, but often occurs at the ends of these bones near growth plates. Osteosarcoma affects children most often between 10- and 25-years old.
This cancer occurs about 50 percent more in males than in females, possibly because of the rapid growth rate at this age. Prior to adolescence, the percentage of affected males and females is equal.
Osteosarcoma cancer cells can also spread (metastasize) to other areas of the body. Most commonly, these cells spread to the lungs. However, bones, kidneys, the adrenal gland, the brain and the heart can also be sites of metastasis.
What Causes Osteosarcoma?
It has been suggested that repeated trauma to an area may be a risk factor for developing this type of cancer. It is uncertain whether trauma is a cause or effect of the disease. Cancer lesions in the bone can make that area of the bone weaker, thus, making injury more likely. However, repeated injuries to a certain area of the bone may lead to an increased production of osteoid tissue to repair the damaged area. The rapid production of osteoid tissue may lead to the malignancy. It is thought, most often, that injury simply brings the condition to attention and has no causal relationship.
Genetics may play an important role in developing osteosarcoma. Children and adults with other hereditary abnormalities, including exostoses (bony growths), retinoblastoma, Ollier's disease, osteogenesis imperfecta, polyostotic fibrous dysplasia and Paget's disease, have an increased risk for developing osteosarcoma.
This form of cancer has also been linked to exposure to ionizing irradiation associated with radiation therapy for other types of cancer (e.g., Hodgkins and non-Hodgkins disease).
What Are the Symptoms of Osteosarcoma?
The following are the most common symptoms of osteosarcoma. However, each child may experience symptoms differently. Symptoms may include, but are not limited to, the following:
- Pain (sharp or dull) at the site of the tumor
- Swelling and/or redness at the site of the tumor
- Increased pain with activity or lifting
- Decreased movement of the affected limb
- A broken bone
The symptoms may have been present over a short period of time or may have been occurring for six months or more. Often, an injury brings a child into a medical facility, where an x-ray may indicate suspicious bone lesions.
The symptoms of osteosarcoma may resemble other conditions or medical problems.
How Is Osteosarcoma Diagnosed?
In addition to a complete medical history and physical examination of your child, diagnostic procedures for oosteosarcoma may include multiple imaging studies of the tumor and sites of possible metastasis, such as:
- X-rays: A diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones and organs onto film. X-rays are used to measure and evaluate the curve.
- Bone scans: Pictures or x-rays taken of the bone after a dye has been injected that is absorbed by bone tissue. These are used to detect tumors and bone abnormalities.
- Magnetic resonance imaging (MRI): A diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body. MRIs are done to rule out any associated abnormalities of the spinal cord and nerves.
- Computed tomography scan (also called a CT or CAT scan): A diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat and organs. CT scans are more detailed than general x-rays.
- Complete blood count (CBC): A measurement of size, number and maturity of different blood cells in a specific volume of blood.
- Blood tests (including blood chemistries)
- Biopsy of the tumor
How Is Osteosarcoma Treated?
Specific treatment for osteosarcoma will be determined by your child's physician based on:
- Your child's age, overall health and medical history
- Extent of the disease
- Your child's tolerance for specific medications, procedures or therapies
- Expectations for the course of the disease
- Your opinion or preference
Treatment may include, but is not limited to, one or more of the following:
- Surgery (e.g., biopsy, resections, bone/skin grafts, limb salvage procedures, reconstructions)
- Radiation therapy (not usually effective and rarely used)
- Resections of metastases (spreading of the tumor to other locations)
- Rehabilitation, including physical and occupational therapy and psychosocial adapting
- Prosthesis fitting and training
- Supportive care (for the side effects of treatment)
- Antibiotics (to prevent and treat infections)
- Continued follow-up care (to determine response to treatment, detect recurrent disease and manage the side effects of treatment)
What Are the Long-Term Effects of Osteosarcoma?
Prognosis for osteosarcoma greatly depends on:
- The extent of the disease
- The size and location of the tumor
- Presence or absence of metastasis
- The tumor's response to therapy, the age and overall health of your child
- Your child's tolerance for specific medications, procedures or therapies.
- New developments in treatment
As with any cancer, prognosis and long-term survival can vary greatly from child to child. Every child is unique and treatment and prognosis are structured around the child's needs. Prompt medical attention and aggressive therapy are important for the best prognosis. Continuous follow-up care is essential for a child diagnosed with osteosarcoma. Side effects of radiation and chemotherapy, as well as second malignancies, can occur in survivors of osteosarcoma. New methods are continually being discovered to improve treatment and to decrease side effects.