Non-Hodgkin's Lymphoma - Diagnosis

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Click the icon to see an image of a lymphangiogram.

Other Advanced Imaging Techniques. A number of advanced imaging techniques, including gallium scintigraphy and positron emission tomography (PET) are proving to be very helpful. Special PET imaging techniques known as FDG/PET scans may be more accurate than CT scans for staging lymphomas and more accurate than gallium scintigraphy in identifying the disease in the bone. They are also very accurate for evaluating the success of chemotherapy in patients who have been treated for lymphomas and for detecting relapsing lymphoma. Gallium scans are also useful for evaluating the success of chemotherapy.

Magnetic resonance imaging (MRI) may be used to detect the spread of the disease to the brain, spine, chest, pelvic, and abdomen. How additional tests such as MRI and PET scanning will impact the management of patients with lymphomas, however, is still unknown.

Click the icon to see an image of a MRI machine.

DNA Tests

Tests of lymphoma's DNA are in use or are being developed to detect particular genetic abnormalities that help determine outlook and may eventually lead to new treatments. Examples of such abnormal genetic arrangements are those that affect normal cell death, resist chemotherapy, or trigger aggressive cancer growth.

An advanced approach called the microarray technique uses chips that contain up to thousands of DNA sequences that represent specific normal and abnormal genes. Such sequences have been compiled for lymphomas. Eventually, experts may be able to match a patient's DNA to these patterns and identify specific subtypes.

Biologic Markers

Biologic markers, called biomarkers for short, are high levels of substances that are released by tumors and indicate the level of cancer activity. Biomarkers can be found in sputum, blood, and tissue samples. Biomarkers can be enzymes, hormones, amino-acid compounds, antigens (identified by antibodies that specifically target them), and growth factors. Some under investigation include:

• CD44. This molecule binds to the surface of cells and may be involved in metastasis. High levels of this molecule may suggest a more aggressive disease.
• BCL-6. This cancer gene is implicated in diffuse large B-cell lymphoma. High levels of this gene in these patients indicate a better outlook after treatment.

Review Date: 01/17/2007
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.