How Doctors Diagnose Lymphoma
Some types of lymphoma are more aggressive and difficult to treat than others, but the earlier lymphoma is diagnosed, the better the chances of survival. Tests are done to pinpoint the disease, and to determine what type and subtype it is and how far along it has progressed. Knowing why and how these tests are performed can help you plan for what’s ahead. In general, a diagnosis of non-Hodgkin or Hodgkin’s lymphoma begins with a physical exam and involves blood tests, imaging exams, and biopsies.
Whether you see your doctor because you’ve not been feeling well or your doctor notices something during a routine visit, all diagnoses begin with a review of your medical history and a physical examination. During your physical exam, your doctor will likely check the following:
Lymph nodes. Lymph nodes are spread throughout your body, acting as filters to remove toxins from the lymph as it circulates. Swollen lymph nodes, particularly in your neck, under your arms, and in your groin, are a sign of infection or inflammation somewhere in your body. In someone with lymphoma, cancerous tumors can form and enlarge the nodes.
Liver and spleen. Your doctor may press down on your abdomen, checking to see if your spleen or your liver is enlarged, which can be due to tumor growth.
Temperature. You may have a fever, usually a low-grade fever.
Blood and Cytogenetic Tests
Blood tests can tell your doctor a lot about how well your body is working. There is no specific test for lymphoma, but blood tests can help rule out other illnesses, such as infections. The most common blood tests done during a physical exam for suspected lymphoma are:
Chemistry panels: These tests look at various components, such as how much protein, glucose (sugar), and cholesterol, is in your blood.
Peripheral blood smear: This test looks at how your red blood cells, white blood cells, and platelets appear under a microscope.
Complete blood count (CBC): Blood checked for a CBC can tell your doctor how many red and white blood cells you have, as well as your hemoglobin (iron) and hematocrit levels.
Cytogenetic analysis: This specialized test looks for chromosomal changes in lymphocytes.
Flow cytometry: This can be done on blood, tissue or bone marrow. It studies the cells for certain characteristics of lymphocytes and can help determine the type and specific subtype of lymphoma. Knowing the specific subtype helps the doctor plan treatment.
Other tests to more fully characterize the subtype could include:
Fluorescence in situ hybridization (FISH): These lab tests can reveal genetic abnormalities in the cells from blood and bone marrow samples.
Immunophenotyping: This test identifies specific proteins on the surface of abnormal lymphocytes, which helps the cancer team narrow down the best treatment for your type of lymphoma.
Karyotype test: This test looks at the number of chromosomes and can identify chromosomal changes in blood and bone marrow cells.
Lymph Node Biopsy
You may need a lymph node biopsy to collect the cells necessary to perform some of the cell and chromosome tests. The biopsy can be done on an entire node that has been surgically removed (an open biopsy), or on a small section of tissue that has been removed from the node (a needle biopsy). The node or tissue is sent to a lab and examined for cancer cells. Looking at the cells themselves and performing other lab tests is the only way to diagnose the type of lymphoma.
An open biopsy requires either a local anesthetic or general anesthetic. The surgeon makes an incision over the area and removes the node or nodes, then sutures (stitches) the incision closed. Or, your surgeon could use a laparoscope, a long, narrow tube with a camera on one end. You would receive a general anesthetic for this procedure. After making a small incision, the surgeon inserts the scope and advances it to the lymph node. Using special tools through the tube, the surgeon removes tissue from the node but the node remains in place.
A needle biopsy is the least invasive method, but doctors do not perform it as frequently as an open biopsy because the results are sometimes not as accurate. After giving you a local anesthetic to numb the area, the doctor inserts a needle into the lymph node and removes some of the tissue.
Bone Marrow Aspiration
Your doctor may want you to have a bone marrow aspiration for testing in the lab. Bone marrow tissue is inside bone. It contains stem cells, which can become fat, cartilage, bone, and different types of blood cells.
The test is usually an out-patient procedure performed by a hematologist or oncologist. The doctor removes the marrow from the posterior iliac crest—towards your back at the top part of your hip. After numbing the area with a local anesthetic, the doctor inserts a sterile needle into the bone and withdraws some of the bone marrow. The procedure takes about 10 minutes.
Bone marrow aspiration can be painful, so your doctor may recommend using an ice pack on the site for the next few days to reduce pain and swelling.
Often called a spinal tap, a lumbar puncture provides samples of cerebrospinal fluid, or CSF. This fluid flows around the spinal cord and brain. Lumbar taps are not a routine test, but your doctor may recommend one to help with diagnosis.
After administering local anesthetic to numb the skin, your doctor inserts a needle into the spinal canal and removes some CSF.
Traditional radiographs (X-rays), ultrasound, CT scan (computed tomography), MRI (magnetic resonance imaging), and PET scan (positron emission tomography) are all imaging tests. These tests can help your doctor determine how far the lymphoma has progressed—the stage of cancer.
If you are experiencing bone pain or your doctor suspects the cancer has reached your bones, a bone scan can confirm or rule this out. A radiology specialist administers an imaging-specific medicine to you. The medicine shows up on a computer monitor as it circulates and travels to the bone.
Waiting for Results
It can take several days or a couple of weeks to gather all information from the tests and confirm the diagnosis. Blood test results may be available the same day, but imaging, biopsy and cytogenetic tests take longer because of the test time and complexity, as well as additional specialists to analyze the information and report it to your doctor.
Ask your doctor beforehand when you might expect the test results, as well as how you will receive them. For example, will it be your doctor or someone else from your doctor’s office calling you with the results? Should you schedule another appointment to discuss the results in person rather than receiving a phone call? Arranging this ahead of time may help ease some anxiety while you wait for results.