Diagnosis of childhood bone cancer
Diagnosing bone cancer usually begins with a visit to your child’s doctor. The doctor will ask about any symptoms your child has and do a physical exam. Based on this information, the doctor may request an x-ray and then refer you to a specialist.
The process of diagnosis may seem long and frustrating. It’s normal to worry, but try to remember that other health conditions can cause similar symptoms as bone cancer. It’s important for the healthcare team to rule out other reasons for a health problem before making a diagnosis of bone cancer.
The following tests are commonly used to diagnose or rule out bone cancer in children. Many of the same tests used to diagnose cancer are used to find out the stage, which is how far the cancer has progressed. The doctor may also order other tests to check the child’s general health and to help plan treatment.
Health history and physical exam
A health history is a record of symptoms, risk factors and all the medical events and problems your child has had in the past. In taking a health history, the doctor may ask questions about a personal history of certain genetic conditions.
A physical exam allows the doctor to look for any signs of bone cancer. During a physical exam, the doctor will check:
- for any swelling or lumps
- how much the child can move the affected arm, leg or joint
Find out more about physical exam.
An x-ray uses small doses of radiation to make an image of the body’s structures on film. Doctors usually x-ray a bone first to find out what is wrong with the bone.
Find out more about x-ray.
Complete blood count (CBC)
A CBC measures the number and quality of white blood cells, red blood cells and platelets. A CBC is done to check if the cancer is in the bone marrow. It is also used as a baseline that doctors can check against during treatment for bone cancer.
Find out more about complete blood count (CBC).
Blood chemistry tests
Blood chemistry tests measure certain chemicals in the blood. They show how well certain organs are functioning and can help find abnormalities. Doctors can use blood chemistry tests as a baseline that they can check against during treatment.
Doctors may measure lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) to stage childhood bone cancer.
Find out more about blood chemistry tests.
A computed tomography (CT) scan uses special x-ray equipment to make 3-D and cross-sectional images of organs, tissues, bones and blood vessels inside the body. A computer turns the images into detailed pictures.
A CT scan is used to check if cancer has spread to the lungs or other organs.
Find out more about CT scan.
Magnetic resonance imaging (MRI) uses powerful magnetic forces and radiofrequency waves to make cross-sectional images of organs, tissues, bones and blood vessels. A computer turns the images into 3-D pictures.
MRI is used to:
- get more details about the bone tumour, soft tissues around the tumour and the bone marrow cavity
- help find small tumours several inches away from the main tumour
- help choose sites for biopsy
- help plan surgery
Find out more about MRI.
A positron emission tomography (PET) scan uses radioactive materials called radiopharmaceuticals to look for changes in the metabolic activity of body tissues. A computer analyzes the radioactive patterns and makes 3-D colour images of the area being scanned.
A PET scan is used to see if the bone cancer has spread to the lungs, other bones or other areas of the body.
A PET scan can be combined with a low-resolution CT scan (called PET-CT scan). Newer machines can do a PET and CT scan at the same time. PET-CT scan is used to examine the metabolic activity of specific areas in the body.
PET-CT may be used to assess response to chemotherapy.
PET-CT is not necessary and remains optional depending on your child’s doctor.
PET scans may not be available in all cancer treatment centres. Find out more about PET scan.
A bone scan uses bone-seeking radioactive materials (called radiopharmaceuticals) and a computer to create a picture of the bones. It is used to see if the cancer has spread to other bones.
Find out more about bone scan.
During a biopsy, the doctor removes tissues or cells from the body so they can be tested in a lab. The report from the lab will confirm whether or not cancer cells are present in the sample.
A biopsy is the only way to make a definite diagnosis of childhood bone cancer. Doctors do an MRI of the tumour to determine the best area to biopsy.
The biopsy is usually done by a surgeon who specializes in bone cancer or under their direction. The surgeon needs to plan both the biopsy and surgery to remove the tumour at the same time because the area where the biopsy is done will be removed during surgery to remove the tumour. Planning the biopsy and surgery together can help prevent complications and can mean less surgery is needed. Planning is especially important to help determine when limb-sparing surgery is a treatment option.
The most common type of biopsy done is a surgical, or open, biopsy. The surgeon cuts through the skin to reach and remove a piece of the tumour from the bone or part of the tumour that has grown into the soft tissues.
Find out more about surgical biopsy.
Core needle biopsy
During a core needle biopsy, the doctor uses a needle to remove a small sample from the tumour. If the tumour is deep in the body, the doctor may use a CT scan to guide the needle into the tumour. This approach is recommended for tumours in certain bones, including the spine or pelvis.
Find out more about core needle biopsy.
Bone marrow aspiration and biopsy
During bone marrow aspiration and biopsy, the doctor removes tissues or cells from the bone marrow so they can be tested in a lab. This test is used to see if cancer has spread to the bone marrow.
Find out more about bone marrow aspiration and biopsy.