Blood Tests

When you have cancer, blood tests are used to watch for treatment side effects and monitor your overall health.

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Blood test results
Complete blood count (CBC)
Blood chemistry tests
How to find the normal range for a CBC or chemistry panel

Blood test results

You may get your blood test results via a patient portal or as a printout at your cancer facility. Some people find it helpful to ask for a copy of their lab results and have a member of their cancer care team go over the numbers with them.

Each lab test has a different range of normal results. Your test results often show where your numbers fall within that range. Reach out to your cancer care team if you have questions about your lab results so they can review them with your specific case in mind.

Getting your results before your health care provider

The United States Office of the National Coordinator for Health Information Technology (ONC) passed the Cures Act. The Cures Act is intended to make it easier for people to see their medical records, clinical notes, and their costs of care. But, it doesn't always allow health care providers to review your test results before you get them. This means that you might see your results on a patient portal at the same time as your health care provider.

Questions to ask before you get your results

People might worry if they see their lab results before they talk to their cancer care team, especially if the results are unclear or seem to show something abnormal.

Talking to the health care provider who is ordering the tests before you get your results might help. Here are some things you might ask about:

What results might I expect? Where and when can I access my test results?
What is a normal or abnormal result? What might this mean for me?
When and how will you contact me to discuss my results?
Who should I call if I see my results first and have concerns about them?

Complete blood count (CBC)

The most common lab test that you’ll have done during treatment is called a complete blood count, or CBC.

Blood is made up of water, proteins, nutrients, and living cells. A CBC tells your cancer care team about the cells in your blood. It measures 3 basic types of blood cells:

Red blood cells
White blood cells
Platelets

Each of these cells has a special purpose. And each can be harmed by cancer and cancer treatments.

RBCs carry oxygen to and carbon dioxide away from the cells in your body. The normal range for RBCs is usually between 4.2 to 5.4 million/mcL for women and 4.7 to 6.1 million/mcL for men. These values may vary between lab facilities.

The CBC measures RBCs in many ways. On your lab report, you might also see values for:

Hemoglobin (Hgb), the part of each RBC that carries iron. The normal range is around 12 to 18 g/dL.
Hematocrit (Hct), the percent of RBCs in the blood. The normal range is around 37% to 52%.

Anemia

When the Hgb and Hct values fall too low, it’s called anemia. The World Health Organization (WHO) defines anemia as:

Hgb less than 12 g/dL and Hct less than 36% in females
Hgb less than 13 g/dL and Hct less than 39% in males

Symptoms may not always occur until your labs are lower than these levels.

When you have anemia, your body is not able to get enough oxygen to all of your cells. This can cause:

Palpitations
Tiredness (fatigue)
Shortness of breath
Lightheadedness or dizziness

WBCs can help fight infection. There are many types of white blood cells and each acts in a special way.

Types of WBCs include:

Neutrophils make up over half of our WBCs. They destroy bacteria.
Lymphocytes can help attack bacteria and viruses.
Monocytes can help kill germs, remove infected cells, and notify other WBCs to assist with treating infections.
Eosinophils help with inflammation, parasites, and allergic reactions.
Basophils help with asthma and allergic reactions.

The number of neutrophils, called the absolute neutrophil count (ANC), can help doctors monitor your health. For a healthy person, the normal range for an ANC is roughly between 2,500 and 6,000. This range might change depending on the lab facility and a person’s specific case.

The ANC is found by multiplying the WBC count by the percent of neutrophils in the blood. For instance, if the WBC count is 8,000 and 50% of the WBCs are neutrophils, the ANC is 4,000 (8,000 × 0.50 = 4,000).

Neutropenia

When the ANC drops below 1,500, it is called neutropenia. Neutropenia can be labeled as mild, moderate, or severe. Your cancer care team will watch your ANC closely because the risk of infection is much higher when the ANC is below 500.

A low WBC count increases your risk of infection. A high WBC count can be a sign that your body is fighting an infection.

Platelets help control bleeding. You may bruise or bleed easily when your platelet levels are low. The risk of bleeding goes up when platelet levels drop below 20,000.

Thrombocytopenia

When your platelet count is low, your cancer care team may call it thrombocytopenia. Thrombocytopenia can be labeled as mild, moderate, or severe.

Blood chemistry tests

Your cancer care team might do blood chemistry tests to check for changes that could be caused by certain treatments or their side effects.

A common blood chemistry test is called a blood chemistry panel. It might also be called a comprehensive metabolic panel, blood chemistry profile, basic metabolic panel, or blood chemistries.

A blood chemistry panel can be used to measure many things like:

Proteins
Fats (lipids)
Sugar (glucose)
Electrolytes, such as potassium, magnesium, sodium, and calcium
Enzymes
Kidney or liver function

Your cancer care team may also decide to only check one part of the chemistry panel. For example, a liver panel or LFT checks your liver health, a kidney function test checks your kidney health, or a lipid panel or cholesterol test checks blood fats.

Abnormal results

If the tests show that certain electrolyte levels are abnormal, your cancer care team may decide to make changes to your care plan. This might mean giving you electrolytes or fluids or changing your medications.

It’s important to get the tests your cancer care team suggests because most of the time you won’t have any symptoms until one or more blood chemistry values are dangerously low or high.

How to find the normal range for a CBC or chemistry panel

Most lab reports list the normal ranges for each test and note whether yours is high or low. Comparing your lab results to the normal ranges makes it easier to ask questions about what the results mean.

Each lab has its own range for what it considers normal values for CBCs and chemistry panel results, often called a reference range. Normal ranges for some tests also vary by age and sex.

Note that results are often given in short form, as shown in the table below. For instance, a WBC result may be shown as 6.2 rather than 6,200, which is why the Units column shows that the value is multiplied by 1000 (x 1000). Results that are high or low might have the letter (H) or (L) after the number, to the side, or in a different column to call attention to the abnormal result.

Common terms and normal values on a CBC report

Test	Units	Normal values	Comments
WBC (white blood cells)	x 1000/mm³	5–10	Number of infection-fighting cells in the blood
RBC (red blood cells)	x 1,000,000/mm³*	4.2–6.1	Number of RBCs, which carry oxygen and carbon dioxide
Hgb (hemoglobin)	g/dL**	12–18	Measure of RBCs
Hct (hematocrit)	%	37–52	Percentage of blood made up of RBCs
Plt (platelets)	x 1,000/mm³	150–450	Number of platelets, which help the blood clot

*mm³ = cubic millimeter or microliter (µL)

**g/dL = grams per deciliter

Example of CBC test results in a person with anemia

Here’s an example of CBC test results in a person with anemia, or a low hemoglobin and hematocrit:

Test	Result	Reference range^#	This result may also be listed as
WBC (white blood cells)	6.2 x 1000/mm³	5–10	6.2K/mm³ or 6,200/mm³ 6.2K/µL or 6,200/µL
RBC (red blood cells)	3.5 x 1,000,000/mm³	4.2–6.1	3.5M/mm³ or 3,500,000/ mm³ 3.5M/µL or 3,500,000/µL
Hgb (hemoglobin)	9 g/dL (L)	12–18
Hct (hematocrit)	28% (L)	37–52
Plt (platelets)	178 x 1000/mm³	150–450	178K/mm³ or 178,000/mm³ 178K/µL or 178,000/µL

^# These number ranges vary somewhat among labs.

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References

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Developed by the American Cancer Society medical and editorial content team with medical review and contribution by the American Society of Clinical Oncology (ASCO).

American Society of Clinical Oncology (ASCO). Understanding your complete blood count. Cancer.net. Content is no longer available.

Department of Health and Human Services Office of the Secretary. 21st Century Cures Act: Interoperability, Information Blocking, and the ONC Health IT Certification Program. 2020. Accessed at https://www.govinfo.gov/content/pkg/FR-2020-05-01/pdf/2020-07419.pdf on February 23, 2026.

Jinna S, Karra S, Penney SW, et al. Thrombocytopenia. Updated December 1, 2025. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026. Accessed at https://www.ncbi.nlm.nih.gov/books/NBK542208/ on March 18, 2026.

Means, RT, Brodsky, RA. Diagnostic approach to anemia in adults. UpToDate. 2025. Accessed at https://www.uptodate.com/contents/diagnostic-approach-to-anemia-in-adults on March 17, 2026.

National Heart, Lung, and Blood Institute. Blood tests. Updated March 24, 2022. Accessed at https://www.nhlbi.nih.gov/health/blood-tests on February 23, 2026.

Waleed, M. Neutropenia. Medscape. Updated May 23, 2024. Accessed at https://emedicine.medscape.com/article/204821-overview#a8 on March 18, 2026.

Last Revised: March 31, 2026

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