People living with a lymphoma diagnosis need numerous laboratory tests before, during, and after treatment — including blood tests. While blood testing can’t diagnose lymphoma, it can help your health care team understand how lymphoma and your treatments are affecting you.

The most common blood test used in the initial investigation for Hodgkin lymphoma or non-Hodgkin lymphoma (NHL) 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.

Here’s a breakdown of what a CBC tests for and what the results can tell your doctors about lymphoma.

What Do Blood Counts for Lymphoma Measure?

A CBC measures how much of each type of blood cell you have in your blood. The three main types of cells are:

• Red blood cells (RBCs) — Also referred to as erythrocytes, their main job is to carry oxygen from the lungs to different parts of the body.
• White blood cells (WBCs) — Also called leukocytes, they are the first line of defense in the immune system, fighting bacteria and viruses that may enter the blood.
• Platelets — Known as thrombocytes, these small cell fragments gather at sites of injury and help the blood clot.

A CBC test will usually measure your hematocrit and hemoglobin levels as well. Hematocrit levels measure what percentage of your blood is currently made up of red cells. Hemoglobin is a protein in RBCs. Measuring hematocrit and hemoglobin can help doctors better understand how well your RBCs are doing their job of carrying oxygen to the tissues in your body.

Normal Ranges for Blood Count Results

The number of each type of cell in the blood is often referred to as the “count.” Lymphoma and its many treatments can affect your blood counts. Usually, blood counts return to normal after cancer treatment is complete.

On a CBC, levels of RBCs, WBCs, and platelets are typically expressed as the number of cells per microliter (mcL) of blood. Normal blood counts are different for everyone. However, per Cleveland Clinic, there are general normal ranges for men, women, and children.

Normal Range for Red Blood Cells (per mcL)

Mayo Clinic provides the following numbers:

• 4.35 million to 5.65 million for men
• 3.93 million to 5.13 million for women
• 4 million to 5.5 million for children

Normal Range for White Blood Cells (per mcL)

Numbers per Mayo Clinic:

• 3,400 to 9,600 for both men and women
• 5,000 to 10,000 for children

WBCs are also measured by the ratio of WBC types — the WBC differential. There are five main types of WBCs: neutrophils, eosinophils, lymphocytes, monocytes, and basophils. According to the Leukemia & Lymphoma Society, the WBC differential in a normal blood count of an adult comprises:

• 55 percent to 70 percent neutrophils
• 20 percent to 40 percent lymphocytes
• 2 percent to 8 percent monocytes
• 1 percent to 4 percent eosinophils
• 0.5 percent to 1 percent basophils

Normal Ranges for Hematocrit Levels (per mcL)

Mayo Clinic has found:

• 38.3 percent to 48.6 percent of total blood count for men
• 35.5 percent to 44.9 percent of total blood count for women
• 32 percent to 44 percent of the total blood count for children

Normal Ranges for Hemoglobin

Hemoglobin is expressed in grams per deciliter (g/dL). Again, these ranges below are per Mayo Clinic.

• 13.2 to 16.6 g/dL for men
• 11.6 to 15 g/dL for women
• 11 to 13 g/dL for children

Normal Ranges for Platelet Counts (per mcL)

• 135,000 to 317,000 for men
• 157,000 to 371,000 for women

Abnormal Blood Count Results

Lymphoma can affect blood cell counts in various ways, and so can many lymphoma treatments such as chemotherapy and radiation therapy.

What do abnormal test results mean? For any given value, a result can be too high, too low, or unusual in relation to another value. For instance, the WBC differential may show an abnormal skew in WBC types. Abnormalities can indicate a problem in the bone marrow, where blood cells are made, or they may mean you have another health condition.

Although normal ranges represent what’s typical for the majority of healthy people, those with underlying health conditions may have lower or higher ranges that are still considered “normal” for them. For example, a person living with heart disease may normally have a higher-than-normal RBC count.

Your CBC results will help your health care team better understand how your lymphoma and treatments are affecting your body. If your results show that your risk for serious side effects or complications is rising, your oncology team may make a change to your treatment options or prescribe other medications to address the problem.

Anemia

You are considered to have anemia if your RBC, hematocrit, or hemoglobin counts are low. Anemia may develop when there are too few RBCs being made in the bone marrow, or when the red cells are being destroyed by disease.

Anemia can also be caused by low levels of iron, B12, or folate in your diet, along with other potential causes — including heavy or persistent bleeding. The primary symptoms of anemia are fatigue, weakness, and pale skin.

Many people with lymphoma experience anemia at some point, either as a side effect of lymphoma treatments or because of the lymphoma itself.

If your RBC count, hematocrit, or hemoglobin are low, your doctor may order a follow-up blood test called a reticulocyte count. Reticulocytes are young, developing RBCs. Counting them can help determine whether the problem is reduced RBC production or if the cells are being destroyed.

High Red Blood Cell Count

If RBC levels are too high, it may mean there’s not enough oxygen in the blood. High RBC levels can also indicate dehydration. In rare cases, a high RBC count may be due to polycythemia vera, a type of blood cancer in which the bone marrow produces too many RBCs.

Overly high RBC counts may be treated by drawing blood until the count is lowered. In some cases, medication might be used to reduce the amount of red cells.

Low White Blood Cell Count

An overall low WBC count, called leukopenia, means that the body has a harder time fighting off infection. If there are fewer neutrophils in WBC counts, the condition is called neutropenia. When neutrophils are low, normal symptoms of infection may not show up because those symptoms are specifically caused by the reaction of neutrophils fighting infection. This reaction can lead to infections lasting longer and being harder to treat.

Low levels of lymphocytes mean the body can’t detect or fight viral infection as easily as usual, as lymphocytes are the cells that react first to viruses. If a test has shown you have low WBC counts and you develop a fever, you should seek immediate medical attention, as this may be the first sign of a serious problem.

High White Blood Cell Count

Certain types of cancer, including lymphoma, may lead to an abnormally high WBC count. A high WBC count, also known as leukocytosis, can also indicate an infection or dysfunction in the immune system. If the lymphocyte count is high, it’s known as lymphocytic leukocytosis.

Low Platelet Count

A low platelet count, or thrombocytopenia, can indicate potential problems with bleeding. People with lymphoma may be at higher risk of low platelet counts. Chemotherapy for lymphoma can also lead to thrombocytopenia.

Thrombocytopenia may develop when too few platelets are being made in the bone marrow or platelets are being destroyed. In some cases, the body does not recognize the platelets as part of the immune system and attacks them. Symptoms of a low platelet count may include:

• Bruising easily
• Excessive bleeding from minor cuts and scrapes
• Weakness or pain in the muscles

Low platelets are commonly treated with transfusion, but your doctor may suggest other methods to reduce the chance of bleeding.

High Platelet Count

A high platelet count is called thrombocytosis and may be the result of cancer. High platelet counts can lead to stroke, heart attack, or a blood clot in a vein. Thrombocytosis is treated with medications that help prevent blood clots or reduce platelet production in the bone marrow.

Pancytopenia

When the body’s levels of RBCs, WBCs, and platelets are all lower than normal, it's referred to as pancytopenia. Pancytopenia can be caused by:

• Leukemia or other diseases of the bone marrow
• Advanced stage of lymphoma
• An autoimmune condition
• A side effect of chemotherapy or radiation treatment
• An infection

Anxiety and Blood Test Results

Blood tests make many people with lymphoma anxious. Results may show how well treatment is working or whether side effects from treatments are becoming more severe. “I had blood work done, and I’m waiting for results. I may have to start doing treatment. That frightens me,” wrote one MyLymphomaTeam member.

“Blood tests came back with great results, so waiting for another round of scans in three months,” shared another member.

MyLymphomaTeam members often provide each other with encouragement and positive words to help get through the stress of blood work and other aspects of living with lymphoma. “You can do it. Stay positive and surround yourself with positive people. It helped me a lot,” one member wrote.

“Keep the faith. Take one day at a time. Do things that make you happy,” another member suggested.

Another member shared their gratitude for their support network: “This group has been a great support. It’s encouraging to hear of others’ experiences!”

Find Your Team

On MyLymphomaTeam, the social network for people with lymphoma and their loved ones, more than 19,000 members come together to ask questions, give advice, and share their stories with others who understand life with lymphoma.

Do you feel anxious when waiting for blood test results? Do you have any tips for managing stress? Share your thoughts in the comments below, or start a conversation by posting to your Activities page.