Waldenstrom’s Macroglobulinemia: Diagnosis

Approved by the Cancer.Net Editorial Board, 12/2018

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If this happens, it is called metastasis. For example, imaging tests can show if the cancer has spread. Imaging tests show pictures of the inside of the body. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know if an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

This list describes options for diagnosing this type of cancer. Not all tests listed below will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and general health

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose Waldenstrom’s macroglobulinemia:

Blood tests. Blood tests may include a CBC (complete blood count) with a differential (classification of the types of white cells) and an examination of the blood with a microscope. Blood tests can help your doctor diagnose Waldenstrom’s macroglobulinemia. An increase in IgM can be found by protein electrophoresis, which is a method of separating proteins in the blood with an electric field.

Biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope. Other tests can suggest that cancer is present, but only a biopsy can make a definite diagnosis. A pathologist then analyzes the sample(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease. The type of biopsy performed depends on the location of the cancer.

The most common type of biopsy for Waldenstrom’s macroglobulinemia is either a bone marrow biopsy or a biopsy of the lymph nodes in the neck, under the arms, or in the groin. A biopsy may also be taken from the chest or abdomen while using a computed tomography (CT or CAT scan) to guide the doctor. A biopsy can also be taken from the stomach or intestine during an endoscopy, a test that allows the doctor to see inside the body using a thin, lighted, flexible tube called an endoscope. More information on bone marrow biopsy and a CT scan is below.

Bone marrow aspiration and biopsy. Lymphoma often spreads to the bone marrow, the spongy material in the center of bones where blood cells are produced. A sample of the bone marrow can be important to diagnose Waldenstrom’s macroglobulinemia, and it can help find out if the cancer has spread.

These 2 procedures are similar and often done at the same time to examine the bone marrow. Bone marrow has both a solid and a liquid part. A bone marrow aspiration removes a sample of the fluid with a needle. A bone marrow biopsy is the removal of a small amount of solid tissue using a different needle.

A pathologist then analyzes the sample(s). A common site for a bone marrow aspiration and biopsy is the pelvic bone, which is located in the lower back by the hip. The skin in that area is usually numbed with medication beforehand. Other types of anesthesia (medication to block the awareness of pain) may also be used.

Tests on the biopsy sample may be done to examine proteins on the tumor cells in order to distinguish Waldenstrom's macroglobulinemia from other types of B-cell lymphomas. These types of tests are called immunohistochemistry and/or flow cytometry.

Molecular testing of the tumor. Your doctor may recommend running laboratory tests on a tissue sample and/or bone marrow sample to identify specific genes, proteins, and other factors unique to the tumor. Molecular tests can also help distinguish Waldenstrom's macroglobulinemia from other B-cell lymphomas. See the Types of Treatment section for more information. Doctors look for a mutation in the MYD88 gene. This mutation is found in Waldenstrom’s macroglobulinemia for most patients, but some patients whose tissue sample has this mutation might have a different lymphoma or other disease.

Computed tomography (CT or CAT) scan. A CT scan takes pictures of the inside of the body using x-rays taken from different angles. A computer combines these images into a detailed, 3-dimensional view that shows any abnormalities or tumors. A CT scan can be used to measure the tumor’s size. Sometimes, special dyes, called contrast mediums, are given before the scan to provide better detail on the image. Dyes are injected into a patient’s vein or given as a pill or liquid to swallow.

Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye is injected into a patient’s vein.

Positron emission tomography (PET) or PET-CT scan. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure just as a PET scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive sugar substance is injected into the patient’s body. This sugar substance is taken up by cells that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. A scanner then detects this substance to produce images of the inside of the body.

Fundascopic evaluation. This exam of the eye is done by an ophthalmologist. An ophthalmologist is a medical doctor who specializes in eye care. This test looks at the blood vessels of the eye.

Urine tests. The doctor tests a urine sample to check for abnormal proteins in the body.

After diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is cancer, these results also help the doctor describe the extent of spread of the cancer. This is called staging.

The next section in this guide is Stages. It explains the system doctors use to describe the extent of Waldenstrom's macroglobulinemia. Use the menu to choose a different section to read in this guide.