Lymphoma is a blood cancer in which lymphocytes (certain types of white blood cells) develop abnormally and crowd out healthy cells. Non-Hodgkin lymphoma (NHL) begins in the lymph nodes, usually affecting lymphocytes. These are key components of your body’s immune system. People living with NHL need numerous laboratory tests — including blood tests — before, during, and after treatment.
Although blood testing can’t diagnose most types of non-Hodgkin lymphoma, it can help your health care team understand how lymphoma and its treatments are affecting you. This is usually not as simple as looking for cancer cells in your blood. If blood tests indicate that there might be a problem, your doctor may next do a physical exam or perform other lab tests to help with the diagnostic process. These tests include:
Several types of blood tests are available for people with NHL. Each can reveal details about different aspects of your general health.
These are the blood tests that your doctor may order to help diagnose and treat non-Hodgkin lymphoma.
The most common type of blood test for non-Hodgkin lymphoma is a complete blood count (CBC), also known as a full blood count. This test uses a blood sample to measure the number of different types of cells in your blood.
A CBC will measure how much of each type of blood cell you have in your blood. There are three main types of cells: red blood cells, white blood cells, and platelets. Here is a breakdown of what is tested for in a CBC and what its results can tell your doctors.
Also called erythrocytes, red blood cells carry oxygen from the lungs all through the body.
In addition to measuring your red blood cell levels, a CBC will usually measure your hematocrit and hemoglobin levels. Hematocrit levels reveal the percentage of your blood that is made up of red blood cells. By measuring hematocrit and hemoglobin, a protein in red blood cells, your doctor can better see how well these blood cells are doing their job.
A CBC can also tell doctors if you are anemic. This means that you do not have enough red blood cells in your bloodstream. Because these cells transport oxygen throughout your body, low levels of them can make you extremely tired. This is one key sign of NHL.
The immune system’s first line of defense involves white blood cells (formerly called leukocytes), which attack bacteria and viruses that enter the blood.
People who have non-Hodgkin lymphoma or are exploring a possible NHL diagnosis may also have a low white blood cell count, which may indicate a vulnerable immune system.
Known as thrombocytes, platelets are small cells that gather at sites of injury and help the blood clot.
Your doctors may also look for low platelet levels during a CBC. If your platelet count is too low, your blood will struggle to clot if you get injured.
Some subtypes of non-Hodgkin lymphoma cause abnormalities in the levels of certain substances (mostly proteins) in your bloodstream. These substances can be measured with tests like immunophenotyping, immunohistochemistry, and flow cytometry.
Some tumor markers are tied specifically to one type of cancer. Others may be linked to several types, and a few may be related to other conditions. Finding these can be useful for diagnosing both B-cell and T-cell lymphoma, monitoring the severity of NHL, or determining how well your lymphoma treatment is working.
Another common blood test for those diagnosed with NHL is a lactate dehydrogenase test. The presence of this enzyme indicates that cells are being destroyed or are dying. People diagnosed with non-Hodgkin lymphoma may have higher levels of lactate dehydrogenase. Although there can be many reasons for you to have more of the enzyme than normal in your bloodstream, one explanation is NHL.
This test is designed to determine how thick your blood is. It can help your doctors monitor your non-Hodgkin lymphoma, particularly if you have been diagnosed with a type called Waldenström’s macroglobulinemia. In this condition, the body produces antibodies that make the blood thick, or viscous. The results of a blood viscosity test can indicate that you should be diagnosed with the condition or tell doctors whether treatments for NHL are working.
If you have Waldenström’s macroglobulinemia, you may also need to undergo antibody testing. Your oncology team may choose to run a serum immunoglobulin test or a serum protein electrophoresis test. These results show doctors which antibodies are present in your bloodstream and their relative concentrations. Once again, this knowledge can help diagnose non-Hodgkin lymphoma, monitor its progression, and determine how well a particular treatment is working.
When doctors test for the presence of urea and electrolytes, they are looking at how well your kidneys are working. Your kidneys are designed to break down these substances and remove them from the body through your urine. If there are high levels of urea or electrolytes in your bloodstream, your kidneys may need extra support. Since non-Hodgkin lymphoma can affect the whole body, these tests can show whether or not the cancer is affecting kidney function.
Most of the time, you won’t need to do anything ahead of time for your blood test. If you do need to prepare, you should receive specific instructions from your doctor or the lab. You may need to fast (refrain from eating or drinking) or adjust your medication schedule — or not take medications at all — for a certain amount of time before the test.
Most blood tests take only a short amount of time to perform. In some cases, you can even get your results within a few minutes. However, you should always discuss your blood tests with your doctor, who is trained to interpret your results in light of all the other medical information available and your medical history.
It’s important that you don’t jump to conclusions or make treatment changes based on a blood test without consulting your doctor first.
At MyLymphomaTeam, you’ll find the support you need. We offer a social network for those who have been diagnosed with lymphoma, those who are being diagnosed, and the people who love them. Join today to ask any questions you might have about lymphoma, participate in ongoing conversations, or share your own story. You’ll meet people from around the world who understand your journey and can help you through it.
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