How Osteosarcoma Is Diagnosed

Osteosarcoma is a rare type of bone cancer that most often affects teenagers and young adults. Approximately 75% of the cases are patients under 25 years of age.

If your doctor suspects osteosarcoma due to persistent symptoms like bone pain and swelling at the suspected tumor site, they may recommend diagnostic tests to help confirm a diagnosis. These may include a blood test and imaging tests, such as X-rays, CT scans, or MRIs.

In this article, you’ll learn more about the diagnostic process.

Self-Examination

At this time, home tests or routine screenings for the diagnosis of osteosarcoma have not been developed. Additionally, many early symptoms of osteosarcoma, such as bone pain and swelling at the site of the tumor, are often overlooked as common childhood bumps or bruises or adolescent growing pains.

In some cases, you may notice a lump or mass beneath the skin that may feel warm to the touch. If symptoms persist, it is important to make an appointment for a checkup with your doctor, as early intervention has been shown to improve chances of survival.

Physical Exam

When you go to the doctor, they will review your health history and ask questions regarding lifestyle and past illnesses or treatments. They will also ask questions regarding your family health history and other hereditary conditions.

The doctor will then conduct a thorough physical examination, carefully checking the soft tissue around the affected bone, feeling for a lump or swelling and looking for redness.

Labs and Tests

Although there is no specific blood test to determine osteosarcoma, your doctor will likely order a urine test and blood tests such as a complete blood cell count (CBC). The results of these tests offer clues as to how well your kidneys and liver are functioning, as well as overall health.

A biopsy is used to diagnose osteosarcoma. During this procedure, a small piece of the tumor is removed via needle or surgery and then examined under a microscope to confirm cells are cancerous.

Two types of biopsies are used to diagnose osteosarcoma:

• Core needle biopsy: In this procedure, a hollow needle is used to remove a small cylinder of tissue from the tumor. Usually, the doctor can aim the needle accurately by feeling around on the surface of the skin. If the tumor can’t be felt near the skin, the doctor can guide the needle to the right spot using an imaging test like a CT scan. A core needle biopsy is often able to be performed with local anesthesia, but general anesthesia may be used in some cases.
• Surgical biopsy: If the tumor is inaccessible to a needle, then a surgical biopsy may be done in an operating room with the patient under general anesthesia. The surgeon will make an incision through the skin and remove a portion of the tumor.
  

Imaging

The doctor will also administer several imaging tests to further diagnose osteosarcoma. These include:

• X-ray: This imaging test is used to look for any abnormal growth in the bones.
• Magnetic resonance imaging (MRI): An MRI machine creates clear images of the internal structures of the body using a computer and large magnet radio waves. This may be ordered if the X-ray is not normal and the doctor needs to see more detail.
• Computed tomography (CT): A computer compiles multiple X-ray images to form a 3D image that shows a detailed view of the internal structures, including the organs, fat, muscles, and bones.
• Bone scan: This test is used to identify bone disorders. During the procedure, a small amount of radioactive material is injected into the veins to help highlight areas of bone damage or disease under a special camera.
• PET scan: In this imaging test, a form of radioactive sugar is injected into the blood to help identify abnormalities in certain metabolic processes. In osteosarcoma cases, a PET scan may be used to help determine if the cancer has spread to other parts of the body.

Differential Diagnosis

Osteosarcoma is usually easily diagnosed. However, depending on the size and location of the cancerous growths, the diagnosis may include tests to rule out other bone cancers, such as Ewing’s sarcoma and malignant fibrous histiocytoma—a type of bone cancer that starts in the soft tissue.

If osteosarcoma is confirmed, the cancer will be graded and staged in order to develop the best plan for treatment.

A Word From Verywell

If you or a loved one receives a diagnosis of osteosarcoma, it can make you feel like the rug has been pulled out from under you. Remember that you do not have to go through this journey alone.

There are resources such as survivor support groups, and you should reach out to your friends and family and tap into these networks for the emotional and physical support that you’ll need through treatment and recovery.

As you or your loved one goes through the diagnosis and treatment plan with your healthcare team, many questions and/or concerns will come up. Write them down and reflect on them prior to your appointments. This will ensure a good discussion with your doctor.

Your caring healthcare team is on your side and can offer comfort and help guide you in the right direction to address any needs that might arise.