Diagnosis is the process of finding the underlying cause of a health problem. The process of diagnosis may seem long and frustrating, but it is important for the doctor to rule out other reasons for a health problem before making a cancer diagnosis. Diagnostic tests for non-Hodgkin lymphoma (NHL) are usually done when:
Many of the same tests used to initially diagnose cancer are also used to determine the stage (how far the cancer has progressed). Your doctor may also order other tests to check your general health and to help plan your treatment. Tests may include the following.
|Diagnostic tests||Staging and other tests|
The medical history is a record of present symptoms, risk factors and all the medical events and problems a person has had in the past. The medical history of a person's family may also help the doctor to diagnose NHL.
In taking a medical history, the doctor will ask questions about:
A physical examination allows the doctor to look for any signs of NHL. During a physical examination, the doctor may:
During a biopsy, tissue is removed from the body so it can be tested in a laboratory. The pathology report from the laboratory will confirm whether or not cancer cells are present in the sample. A lymph node biopsy is done to diagnose NHL. All or part of a lymph node may be removed. The type of biopsy done depends on where the enlarged lymph nodes are:
A lymph node biopsy is the only way to make a definite diagnosis of lymphoma and to find out the subtype.
A biopsy may be taken from a lymph node in the neck, under the arm or in the groin. It may also be taken from the chest or abdomen during a computed tomography (CT) scan. If the lymph node is near the surface of the skin, the lymph node biopsy may be done with a local anesthetic. If it is deeper inside the body and not as easy to get to, the doctor may need to use a general anesthetic.
Special studies, such as molecular genetic studies, may be done on biopsy samples to help identify which lymphoma subtype a person has. Some of these techniques identify chromosomal abnormalities or genetic changes related to a lymphoma. Other studies look for certain proteins or substances on the surface of lymphoma cells.
A bone marrow aspiration and biopsy is a procedure in which a small amount of bone marrow and bone is removed for microscopic examination. It may be used to diagnose NHL, but it is most useful for staging because NHL can spread to the bone marrow.
Lymphoma can develop in organs or tissues outside the lymph nodes (extranodal lymphoma). Biopsies of other tissues or organs may be needed to determine if lymphoma or another type of cancer is present. Sometimes these biopsies may be done to stage the lymphoma. Organs or tissues that may need to be biopsied to rule out or confirm NHL include:
Some biopsies, such as those taken from the stomach or intestine, can be done during an endoscopy procedure.
A complete blood count (CBC) measures the number and quality of white blood cells, red blood cells and platelets. A CBC is done to:
Blood chemistry tests measure certain chemicals in the blood. They show how well certain organs are functioning and can also be used to detect abnormalities. They are used to help stage NHL and to check liver and kidney function.
An HIV blood test may be done if doctors suspect the lymphoma is related to AIDS. This test measures the level of HIV antibodies in the blood. A high level of these antibodies means the body has been infected with HIV.
People with lymphoma are tested for hepatitis B. If they have a positive test result, they are at risk for developing hepatitis. This risk increases if they have NHL because they are likely to be treated with drugs that suppress the immune system, such as chemotherapy drugs, corticosteroids, monoclonal antibodies or radioimmunotherapy. If people test positive for hepatitis B, they are given a drug to treat hepatitis B infection while receiving treatment for NHL.
An x-ray uses small doses of radiation to make an image of the body's structures on film. A chest x-ray is used to:
A CT scan uses special x-ray equipment to make 3-dimensional and cross-sectional images of organs, tissues, bones and blood vessels inside the body. A computer turns the images into detailed pictures. It is used to:
MRI uses powerful magnetic forces and radio-frequency waves to make cross-sectional images of organs, tissues, bones and blood vessels. A computer turns the images into 3-dimensional pictures. It is used:
MRI may not be available in all treatment centres.
Ultrasound uses high-frequency sound waves to make images of structures in the body. It is used to:
A lumbar puncture (LP) involves removing a small amount of cerebrospinal fluid (CSF) from the spine for microscopic examination. It is used to:
A bone scan uses bone-seeking radioactive materials (radiopharmaceuticals) and a computer to create a picture of the bones. It is used:
A PET scan uses radioactive materials (radiopharmaceuticals) to detect changes in the metabolic activity of body tissues. A computer analyzes the radioactive patterns and makes 3-dimensional colour images of the area being scanned. It may be used to:
PET scans are often done instead of gallium scans to evaluate lymphoma.
The role of PET scanning in NHL is still being refined. PET scans are not available in all treatment centres.
The Canadian Cancer Society provides helpful information about government income programs, financial resources and other resources available to families struggling to make sense of the personal financial burden they face.