What Blood Tests Are Used to Diagnose Lymphoma?

Doctors will sometimes use blood tests when diagnosing lymphoma. Blood tests that can help doctors diagnose lymphoma include the following:

• Complete blood count

• Blood chemistry tests

• Immunophenotyping

• LDH test

• Serum immunoglobin test

Learn more about what these blood tests indicate lymphoma below.

Complete Blood Count (CBC)

This type of test is used to check different features and parts of the blood, including measuring the number and types of cells in the blood. It measures the number of red blood cells, white blood cells, and platelets in the blood, as well as the amount of hemoglobin in the red blood cell. For a person with lymphoma, low blood cell counts may be an indication that the lymphoma has grown into the bone marrow, thereby affecting new blood cell formation.

Blood Chemistry Tests

A doctor may further recommend a blood chemistry test to determine if essential organs like the liver and kidney are functioning properly. It may involve checking the levels of electrolytes or products released by the organs into the body. An abnormal range could indicate a health complication.

Immunophenotyping

Also a type of flow cytometry, immunophenotyping is sometimes applied in the diagnosis of lymphoma. It involves using antibodies to identify and classify lymphoma cells based on the type of antigens or markers on the cell surfaces.

LDH Test

Lactate dehydrogenase (LDH) levels are often higher in people with lymphoma. Doctors may order a blood test to check for the LDH level.

Serum immunoglobulin Test

This test measures the level of antibodies in the blood. Certain antibodies may be high in some types of lymphoma. Also, antibody levels may go low after some lymphoma treatments, leaving the body more susceptible to infections.

There are different types of lymphomas, and there are different ways physicians diagnose them, including through biopsies and imaging tests.

“Lymphomas are a very large and complicated category of cancer, with over 60–70 different varieties. Non-Hodgkin Lymphoma (NHL) is the most common type of lymphoma, accounting for roughly 80% of all lymphomas," said Adeel Khan, MD, MPH, MS, hematologist-oncologist and assistant professor at the University of Texas Southwestern Medical Center. Hodgkin lymphoma (HL) is the other subtype that is less common and less aggressive.

Healthcare professionals do not always use blood tests to diagnose cancers. “While blood tests are necessary during the work-up and evaluation of any hematologic malignancy such as leukemia, myeloma, and lymphoma, the chief diagnostic test is typically a tissue biopsy,” Dr. Adeel explained.

However, blood tests, such as blood chemistry tests and complete blood counts (CBC), are sometimes included as part of a lymphoma diagnosis as they can help determine how advanced the condition is and how best to treat it.

Non-Hodgkin Lymphoma Diagnosis

Doctors may recommend the following tests to diagnose and determine the NHL stage:

• Lymph node biopsy

• Bone marrow biopsy

• Blood panel tests, which can include CBC, LDH, and C-reactive protein (CRP) test

• Imaging tests, such as X-ray, ultrasound, Positron emission tomography (PET), and computed tomography (CT) scan

• Spinal tap

• Chromosome tests, such as polymerase chain reaction (PCR), cytogenetic analysis, and fluorescence in situ hybridization (FISH)

• Other tissue and blood tests like immunohistochemistry and immunophenotyping

Hodgkin Lymphoma Diagnosis

Doctors often use biopsies to check whether a person has NHL or HL. When cancer cells are viewed under a microscope, the hallmark of a Hodgkin’s lymphoma diagnosis is the presence of Reed-Stenberg cells, which are large abnormal lymphocytes with more than one nucleus.

The diagnostic method for HL is similar to that for NHL. It often involves “excisional lymph node biopsy, bone marrow biopsy, flow cytometry of the bone marrow, cytogenetics, FISH studies, and a PET CT scan,” said Milan Sheth, MD, quadruple board certified in internal medicine, hematology, oncology, and palliative care, at the MemorialCare Todd Cancer Institute at Long Beach Medical Center in Long Beach, California.