Understanding Lab and Imaging Tests
About Blood Tests
About Bone Marrow Tests
About Imaging Tests
Preparing for Tests
Keeping Track of Test Results
Questions to Ask Your Healthcare Provider about Lab and Imaging Tests

Understanding Lab and Imaging Tests

Blood, bone marrow and imaging tests are important tools that help doctors diagnose, treat and manage blood cancers, as well as many other health conditions. Healthcare providers consider these test results along with information from your physical examination and detailed medical history to

• Assess your health
• Decide whether additional tests are needed
• Help guide treatment decisions
• Track your health during treatment and after treatment is completed.

Your doctor may also order additional tests if you have multiple medical conditions such as heart disease, kidney disease, diabetes or other illnesses that may affect the body's ability to fight infection. With respect to a blood cancer diagnosis, test results can be used to

• Confirm a diagnosis, the specific subtype of cancer and the staging of the disease
• Determine a patient's risk and expected outcome (prognosis)
• Guide treatment decisions
• Observe a patient's condition without giving treatment (for patients who are in "watch and wait")
• Measure response to treatment during and after therapy.

Tests may be done in your doctor's office, at an outpatient clinic, at a lab, or in the hospital. Always check with your doctor for specific pretest instructions. For example, you may need to fast (not consume any food or beverages) for a specified number of hours before certain tests.

Any time tests are needed, it can cause anxiety. Keep in mind that many of the tests mentioned below are used not only to identify and track blood cancers but also other more common conditions. No single test result provides all the answers. Most results need to be considered along with other reports and within the context of your overall health.

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About Blood Tests

When your doctor or another healthcare provider orders a blood test, he or she chooses from a list of tests that can provide important clues about what's going on inside your body.

The most common blood test (called a complete blood count or CBC) measures the number of red cells, white cells and platelets in the blood. In addition to blood cell counts, there are many chemicals in the blood that can indicate how other parts of the body are functioning, including your liver, kidney, heart and lungs.

Blood cancers affect the blood in different ways. If a doctor suspects a patient may have cancer, he or she may test the blood for biomarkers. The presence of certain biomarkers—substances that can be found in the blood, urine or tissues of some patients with cancer—may indicate cancer activity. A number of behaviors or conditions can affect blood cell counts including

• Illness or stress
• Medicines you take, especially chemotherapy
• Street drugs (for example marijuana or inhalants)
• Foods and beverages, including alcohol
• Intense exercise
• Smoking.

Blood cancers affect cell counts in various ways. Measures may be lower or higher than usual depending on a number of factors. Cancer treatments, such as chemotherapy, drug therapy or radiation can also affect your blood counts but these usually return to normal once treatment is completed. Be sure to discuss blood cells counts with your doctor.

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About Bone Marrow Tests

Bone marrow tests allow doctors to look at the fluid and tissue in the marrow to determine whether cancer or another disease is affecting blood cell production and/or the structure of the marrow. Marrow tests can help determine the type and extent of the disease.  Blood cells are made in the marrow. Certain changes to blood cells can be detected in marrow samples before they can be detected in blood samples.

Bone marrow aspiration and a bone marrow biopsy are two tests that are usually done together. Samples of fluid, tissue and cells are examined under a microscope to look for chromosome changes (cytogenetic analysis) and other changes in the cells.

These tests are also used to evaluate the response to cancer treatment by looking at whether marrow function is beginning to return to normal. This is often done in combination with a white cell differential (also known as "CBC plus differential" or "differential").

Marrow samples may also be used for immunophenotyping, a test that can be used to identify cells based on certain biomarkers on the cell's surface. In some cases, blood samples are also used for cytogenetic testing and immunophenotyping.

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About Imaging Tests

Imaging or radiology tests create pictures of the chest, abdomen, head, neck and other parts of the body. These tests use different forms of energy (x-rays, sound waves, radioactive particles, or magnetic fields) that are passed through the body.

Examples of imaging tests include

• X-rays
• Ultrasound
• CT (computed tomography) scans
• MRI (magnetic resonance imaging)
• FDG-PET (fluorodeoxyglucose with positron emission tomography).

Imaging tests are generally used to look for signs of disease or to check if the cancer (tumors or masses of cells) has spread to other areas, such as the lymph nodes, chest or lungs. Your doctor may order an imaging test "with contrast" to make certain organs and tissues in the body easier to see.

The contrast dye used is usually a liquid that is swallowed or injected into a vein or port. You will get specific pre-test instructions from your healthcare provider. For example, it's important that you do not move during an imaging test so the resulting pictures are clear. Be sure to tell your doctor if you are or might be pregnant, because many imaging tests use small amounts of radiation.

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Preparing for Tests

Many people feel some stress or anxiety about having a test or getting test results. It's important to discuss any concerns that you may have with your doctor and ask questions so that you understand why a specific test is being ordered and what to expect.

You may have concerns or questions about

• The safety of the test
• Your comfort during and after the test
• Whether you need to do anything beforehand to prepare for the test
• Whether you will need someone to pick you up after the test
• How long you'll have to wait for the test results
• Whether you need to call for the results or if your doctor's office will call you
• When you'll be able to discuss the test results with your doctor.

Many people are uncomfortable about having their blood drawn, getting injections (shots) or being in an enclosed space (a part of certain imaging tests). Make sure you discuss any concerns with your doctor or mention them to the staff when you schedule your appointment.

Parents often have to calm their child's fears about tests. For guidance, see The Leukemia & Lymphoma Society's (LLS) free booklet Coping with Childhood Leukemia and Lymphoma.

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Keeping Track of Test Results

If someone has a blood cancer, lab and imaging tests are important tools that help the healthcare team identify problems early and, if needed, direct treatment decisions for individual patients. Here are some helpful tips to get organized and manage your health:

• Ask your doctor why certain tests are being done and what to expect.

• Discuss test results with your healthcare provider. Understanding these results can help you be an active partner in your care. For instance, for blood tests, ask your nurse or doctor to review your measures and how they compare to the lab's normal ranges.

• Find out whether additional follow-up tests are needed and when. Follow-up tests and appointments are sometimes needed to make sure health problems are identified early on and to make sure a patient is responding to treatment. These appointments also provide an opportunity to talk with your providers about any health concerns or questions you may have.

• Depending on the type of test and why it's been ordered, you may want to bring someone with you to listen, help ask questions and take notes. He or she can also provide emotional support.

• Ask for and keep copies of lab reports from your healthcare providers. You might consider creating your own file folder or three-ring binder. Choose a system that works best for you. Be sure to organize test reports by date (chronological) order so they are easy to find. Starting a folder or binder will help you

• Keep all of your test results and health information in one place
• Compile information from different physician offices
• Play an active (and more informed) role in your care
• Refer to reports when talking with your healthcare team or caregivers
• Track trends or changes over time. For example, levels of B12, iron or folate, can play a role in anemia (low red blood cell production).

As you organize your health records, you'll save time and feel more knowledgeable about your health.

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Questions to Ask Your Healthcare Provider about Lab and Imaging Tests

Asking questions can help you understand why a certain test is necessary and will help you take an active role in your care. Ask your healthcare provider to explain in another way if you don't understand his or her answers. Bring your questions to your next healthcare appointment or have them at hand if you are speaking to your provider by phone.

Click here for a printable question guide for discussing lab and/or imaging tests with your healthcare provider.

See the free LLS booklet Understanding Lab and Imaging Tests for more information.

Contact Us

The Leukemia & Lymphoma Society
1311 Mamaroneck Ave.
White Plains, NY 10605

or call the Information Resource Center at (800) 955-4572.

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