Osteosarcoma is a type of bone cancer that usually develops in the long bones of the arms or legs, but it can also occur in other bones such as the pelvis or spine. It typically affects children and young adults between the ages of 10 and 25 and is more common in males than females.
Osteosarcoma develops from the cells that form new bone tissue, and it often causes bone pain and swelling. In some cases, cancer may spread to other parts of the body, such as the lungs or other bones.
Types of Osteosarcoma
There are several different types of osteosarcoma, which are classified based on the location and characteristics of the tumor –
- Conventional osteosarcoma – This is the most common type of osteosarcoma, accounting for about 70% of all cases. It typically arises in the long bones of the body, such as the arms or legs.
- Intracortical osteosarcoma – This type of osteosarcoma is a rare variant that arises within the bone cortex, which is the outer layer of the bone. It tends to be slow-growing and has a better prognosis than conventional osteosarcoma.
- Juxtacortical osteosarcoma – It arises in the tissues surrounding the bone, such as the periosteum or the soft tissues adjacent to the bone. It is also known as parosteal osteosarcoma or periosteal osteosarcoma.
4. Telangiectatic osteosarcoma – This is a rare type of osteosarcoma that is characterized by large cystic areas within the tumor. It tends to be more aggressive and has a poorer prognosis than other types of osteosarcoma.
5. Small cell osteosarcoma – It is characterized by small, uniform cells. It tends to be more aggressive and has a poorer prognosis than conventional osteosarcoma.
6. Secondary osteosarcoma – This type of osteosarcoma arises as a result of radiation therapy or chemotherapy for another type of cancer. It is less common than primary osteosarcoma but tends to be more aggressive and more resistant to treatment.
Overall, the specific type of osteosarcoma can influence the treatment options and overall prognosis for the patient. A team of specialists will typically perform a thorough evaluation to determine the specific characteristics of the tumor and develop an appropriate treatment plan.
Causes and Risk Factors
The direct cause of osteosarcoma is not yet known, but there are several risk factors that have been identified that can cause osteosarcoma including –
- Genetic factors – Certain genetic conditions such as Li-Fraumeni syndrome and hereditary retinoblastoma increase the risk of developing osteosarcoma.
- Previous radiation therapy – People who have received high doses of radiation therapy for other conditions, such as other types of cancer, may be at an increased risk of developing osteosarcoma.
- Age and gender – Osteosarcoma is more commonly diagnosed in children and young adults, and males are more likely to develop the disease than females.
- Bone disorders – Certain bone disorders, such as Paget’s disease, may increase the risk of developing osteosarcoma.
- Lifestyle factors – Some studies have suggested that certain lifestyle factors, such as smoking and exposure to environmental toxins, may increase the risk of developing osteosarcoma.
Most people who have one or more of these risk factors do not develop osteosarcoma. Additionally, many people who are diagnosed with osteosarcoma do not have any identifiable risk factors.
The symptoms of osteosarcoma can vary depending on the location and stage of the cancer. Some common symptoms may include –
- Pain – Pain in the affected bone is often the first symptom of osteosarcoma. The pain may be mild at first and gradually become more severe over time.
- Swelling – Swelling around the affected bone is another common symptom of osteosarcoma. The swelling may be tender to the touch and may feel warm.
- Limited movement – As cancer grows, it can limit the range of motion in the affected joint or limb. This can make it difficult to perform normal activities such as walking, bending, or lifting.
- Fractures – Osteosarcoma weakens the bone, which can increase the risk of fractures. A sudden fracture without any obvious cause may be a sign of osteosarcoma.
In some cases, osteosarcoma can cause other symptoms such as fatigue, weight loss, and fever. Many of these symptoms can be caused by other conditions as well, so it is important to consult a doctor if you are experiencing any of these symptoms. Early diagnosis and treatment can improve the outcome for people with osteosarcoma.
Diagnosis and Tests
If your doctor suspects osteosarcoma, they will likely perform several tests to confirm the diagnosis. These may include –
- Physical exam – Your doctor will perform a physical exam to look for signs of osteosarcoma, such as swelling, tenderness, or limited range of motion in the affected bone.
- Imaging tests – Imaging tests such as X-rays, CT scans, MRI scans, or bone scans can help to identify the location and size of the tumor, as well as determine if cancer has spread to other parts of the body.
- X-rays – X-rays are often the first imaging test used to diagnose osteosarcoma. X-rays can show the location and size of the tumor, as well as any damage or changes in the surrounding bone.
- Computed Tomography (CT) scans – A CT scan can help determine if cancer has spread to nearby tissues, such as muscles and blood vessels, or to nearby bones. It can also help detect the presence of any metastases or tumors that have spread to other parts of the body, such as the lungs.
- Magnetic Resonance Imaging (MRI) scans – An MRI scan uses a powerful magnetic field and radio waves to create detailed images of the body’s soft tissues, such as muscles and tendons, as well as the bones. MRI scans provide more detailed images of the soft tissues than other imaging tests, making it easier to see the extent of the tumor and any damage it may have caused.
- Bone scan – A bone scan is a type of imaging test that is often used to help diagnose and stage osteosarcoma. A small amount of radioactive material is injected into the patient’s bloodstream, which then travels to the bones. A special camera is used to detect the radioactive material and create images of the bones.
- Biopsy – A biopsy involves removing a small sample of the tumor for analysis under a microscope. This is the most definitive way to diagnose osteosarcoma and to determine its stage and grade.
- Blood tests – Blood tests may be performed to check for certain markers that are associated with osteosarcoma, such as alkaline phosphatase.
Once a diagnosis of osteosarcoma has been made, additional tests may be performed to determine if cancer has spread to other parts of the body. This may include a chest CT scan or other imaging tests. The results of these tests will help your doctor to develop a treatment plan that is tailored to your specific needs.
The treatment of osteosarcoma usually involves a combination of surgery, chemotherapy, and sometimes radiation therapy. The specific treatment plan will depend on the location and size of the tumor, the extent of cancer, and the patient’s overall health and medical history.
- Surgery – is usually the first line of treatment for osteosarcoma. The goal of surgery is to remove as much of the tumor as possible while preserving as much of the surrounding bone and tissue as possible. In some cases, amputation of the affected limb may be necessary if the tumor is too large or if it has spread to nearby blood vessels or nerves. However, advances in surgical techniques have made limb-sparing surgery possible in many cases, allowing patients to retain full use of their affected limbs.
- Chemotherapy – is often used before or after surgery to help kill any remaining cancer cells and to reduce the risk of cancer coming back. Chemotherapy drugs are usually given in cycles, with a period of treatment followed by a period of rest to allow the body to recover.
- Radiation therapy – may also be used in some cases, either before or after surgery, to help shrink the tumor and kill any remaining cancer cells. Radiation therapy is usually reserved for cases where the tumor cannot be surgically removed or when surgery is not an option.
Research studies are available to test new treatments for osteosarcoma. Patients who are eligible for clinical trials may be able to receive innovative treatments that are not yet available to the general public.
The outlook for patients with osteosarcoma depends on several factors, including the location and size of the tumor, whether cancer has spread to other parts of the body, and the patient’s age and overall health.
Overall, the prognosis for osteosarcoma is generally better in younger patients, as they tend to respond better to treatment and are more likely to tolerate aggressive therapies such as chemotherapy. Patients who have smaller tumors that have not spread to other parts of the body also tend to have a better prognosis than those with larger, more advanced tumors.
With current treatments, the overall 5-year survival rate for patients with osteosarcoma is around 70%, according to the American Cancer Society. However, the outlook can vary widely depending on the specific circumstances of each patient. Patients with osteosarcoma must receive prompt and appropriate treatment from a team of specialists with experience in treating this type of cancer. Close monitoring and follow-up care are also important to ensure the best possible outcome for the patient.