Diagnosing Non-Hodgkin Lymphoma in Children

Childhood non-Hodgkin lymphoma is a cancer of the lymph system, which is composed of tissues and organs that help the body fight foreign substances, such as viruses or bacteria.

Non-Hodgkin lymphoma starts in white blood cells called lymphocytes. It is more common in children than Hodgkin lymphoma and affects more boys than girls. Most types are fast-growing and require intensive chemotherapy treatment.

There is no known cause, but risk factors in children include having an infection with the Epstein–Barr virus or HIV, or taking medications that suppress the immune system, such as those needed after an organ transplant.

Signs and Symptoms

Some of the most common symptoms of non-Hodgkin lymphoma in children include enlarged or swollen lymph nodes in the neck or abdomen, chills, chronic fever, fatigue, night sweats, shortness of breath, a swollen abdomen, unexplained weight loss, and swelling in the arms, chest, face, or neck.

Children with non-Hodgkin lymphoma sometimes show subtle signs, such as fatigue, noticeable mainly to parents and doctors. Symptoms can overlap with those of other conditions, so it’s important that you visit your child’s pediatrician, who takes a medical history, performs a physical exam, and orders blood tests to check for evidence of lymphoma or leukemia.

At the Stephen D. Hassenfeld Children’s Center for Cancer and Blood Disorders, part of Hassenfeld Children’s Hospital at NYU Langone, pediatric hematologist–oncologists diagnose childhood non-Hodgkin lymphoma by taking a medical history, performing a physical exam, and ordering diagnostic tests. Childhood non-Hodgkin lymphoma is typically a fast-growing cancer, so our specialists work quickly to ensure that your child starts the necessary treatment as soon as possible.

Diagnostic Tests

Our pediatric oncologists perform certain tests and work with expert pathologists to identify the type of lymphoma your child has and create the best treatment plan.

Blood Tests

Our specialists take a sample of your child’s blood to check for the number and type of white blood cells in it. This can help differentiate lymphoma from leukemia, the most common childhood cancer. They also check the number of red blood cells and platelets and look for a high levels of uric acid and lactate dehydrogenase, or LDH, an enzyme that may signal fast-growing lymphoma.

CT–PET Scans

Our specialists now typically use a combination of a CT and a PET scan in diagnosing childhood non-Hodgkin lymphoma. In a CT–PET scan, two types of imaging tests provide information about the body. The same machine is used in both tests.

The CT scan uses X-rays to produce multiple images of the organs in the body and to detect tumors. Your child’s doctor may ask him or her to swallow a thick liquid, a contrast agent that makes the organs more visible during the CT test. CT scans assess the size of organs and any masses.

For the PET scan, a small amount of a radioactive sugar is injected into a vein. The substance collects around tumor cells, allowing them to be detected by a computer during the scan. The computer creates three-dimensional images showing how different tissues metabolize the sugar.

Because cancerous tissue processes sugar more quickly than healthy tissue does, cancer cells and tumors appear as brighter areas on the scan, helping doctors distinguish between cancerous and noncancerous tissue.

Sedation or, for very young children, general anesthesia, may be used under the guidance of a pediatric anesthesiologist. If you are accompanying your child to the test, you must wear a lead apron to prevent radiation exposure. Pregnant women are advised not to be in the room while the machine is operating. The test takes about 45 minutes.

CT–PET scans may also be used later to measure the effectiveness of treatment.

Excisional Biopsy

Doctors use this procedure to distinguish between noncancerous and cancerous tissue. They look for lymphoma cells and rule out the presence of Reed–Sternberg cells, which typically indicate Hodgkin lymphoma. The doctor surgically removes an enlarged lymph node, which is then sent to a lab and analyzed under a microscope. Your child’s doctor performs this biopsy while a pediatric anesthesiologist oversees the child’s sedation or anesthesia.

Bone Marrow Aspiration and Biopsy

Results of a bone marrow aspiration and biopsy can help doctors determine how advanced childhood non-Hodgkin lymphoma is—and how it should be treated. During this test, which is performed using sedation, your child’s doctor uses a small needle to remove a sample of bone marrow from the pelvic bone in the lower back. A hematopathologist, who specializes in analyzing cells to diagnose cancers of the blood, then reviews the cells under a microscope in a laboratory.

If cancer cells are found in the bone marrow, more aggressive treatment may be needed. If many cancer cells are detected in the bone marrow, the condition is classified as leukemia.

Lumbar Puncture

This test can help determine if cancer cells are present in the central nervous system, which can influence the type of treatment your child receives. In a lumbar puncture, a thin needle is inserted into the lower back to withdraw spinal fluid to be tested in a laboratory. It is performed with sedation.