Non-Hodgkin (Non-Hodgkin's) Lymphoma
A lymphoma is a cancer of the lymphatic system, which is a part of the body's immune system. It helps filter out bacteria, viruses, and other unwanted substances.
Most of the time, we're not aware of the inner workings of our lymphatic systems unless the lymph nodes, or glands, become swollen. This often happens during illness — a sign that the lymphatic system is working hard to filter harmful things out of the body.
What Is Non-Hodgkin (Non-Hodgkin's) Lymphoma?
Non-Hodgkin lymphoma (also called non-Hodgkin's lymphoma) is a disease in which cancer cells form in the lymphatic system and start to grow uncontrollably.
There are several different types of lymphomas. Some involve lymphoid cells (called Reed-Sternberg cells) and are grouped under the heading of Hodgkin lymphoma.
All other forms of lymphoma fall into the non-Hodgkin grouping. The different forms of non-Hodgkin lymphoma are marked by the malignant growth of white blood cells that live in the lymph nodes, called lymphocytes.
What Causes Non-Hodgkin Lymphoma?
The exact cause of non-Hodgkin lymphoma is unclear. But doctors have identified some risk factors, such as:
- having conditions that weaken the immune system, like AIDS
- taking immune-suppressing medicines after organ transplants
- exposure to certain viruses, such as Epstein-Barr virus (the virus that usually causes mono)
- having a sibling with the disease
Also, kids who have had either chemotherapy or radiation treatments for other types of cancer seem to have a higher risk of developing lymphoma later in life.
In most cases of non-Hodgkin lymphoma, doctors never find a specific cause. But that doesn't change the fact that experts are getting better and better at treating it.
Regular pediatric checkups may spot early symptoms of lymphoma in cases where the cancer is linked to the treatments or conditions mentioned above.
What Are the Signs and Symptoms of Non-Hodgkin Lymphoma?
Symptoms of non-Hodgkin lymphoma vary depending on the type of lymphoma and where the tumor is. Some kids might have stomach pain, constipation, and decreased appetite. Others may have trouble breathing, difficulty swallowing, coughing or wheezing, or chest pain.
Other symptoms can include:
- painless swollen lymph nodes
- fever, chills, or night sweats
- itchy skin
- weight loss despite eating normally
- bone or joint pain
- frequent infections
Commonly, the first symptom is swollen lymph nodes, usually in the neck, armpits, and groin. Of course, swollen lymph nodes don't usually mean cancer — they're most often a sign of a common illness, like an infection.
In fact, all of the symptoms of non-Hodgkin lymphoma can be caused by other conditions, which is why only a doctor can determine what's really wrong.
How Is Non-Hodgkin Lymphoma Diagnosed?
If non-Hodgkin lymphoma is suspected, a doctor will do a thorough evaluation, which includes getting a medical history and doing a physical exam. Then the doctor might refer the child to an oncologist (a doctor who specializes in cancer and its treatments).
The oncologist may do a lymph node biopsy. In a biopsy, a tiny bit of tissue is removed and looked at in a lab. Depending on the type of biopsy, the child may get local anesthesia (where only a part of the body is numbed) or general anesthesia (where the patient is asleep) to ensure there's no pain.
Biopsies used to test for non-Hodgkin lymphoma include:
- excisional biopsy: removal of an entire lymph node
- incisional biopsy: removal of only a part of the lymph node
- bone marrow biopsy: using a needle to take samples of the soft tissue inside a bone
- fine needle aspiration: using a very thin needle to suction out a small amount of tissue from the lymph node
Other tests used to diagnose non-Hodgkin lymphoma include:
- blood tests
- a chest X-ray
- a computerized tomography (CT or CAT) scan, which rotates around the patient and creates an X-ray picture of the inside of the body from different angles
- an ultrasound, which uses high-frequency sound waves to create pictures of the inside of the body
- a magnetic resonance imaging (or MRI) scan, which uses magnets and radio waves to allow doctors to see inside the body
- a bone scan to detect bone changes
- a positron emission tomography (PET) scan, which can tell the difference between normal and abnormal cells based on metabolic activity
- a gallium scan, if the doctor thinks a PET might not be a good option. In this test, a radioactive material called gallium is injected into the body to help show tumors and inflammation.
How Is Non-Hodgkin Lymphoma Treated?
Treatment of childhood lymphoma is largely determined by staging. Staging is a way to figure out how much the disease has affected the body.
The four stages of lymphoma range from Stage I (cancer involving only one area of lymph nodes or only one organ outside the lymph nodes) to Stage IV (cancer has spread, or metastasized, to one or more tissues or organs outside the lymphatic system). The stage at diagnosis can help doctors choose the right treatments.
The most common treatment for non-Hodgkin lymphoma is chemotherapy (medicines that kill or stop the growth of cancer cells), though some patient get radiation therapy (high-energy X-rays used to kill cancer cells).
Kids who receive very aggressive treatments may have bone marrow or stem cell transplants to replace cells damaged by high doses of chemo or radiation. In a transplant, doctors put healthy new bone marrow or blood cells into the patient's bloodstream through an IV. These new cells are either taken from the patient before treatment or donated by someone else.
In a few special situations (such as high-risk patients or those whose cancer has come back), doctors will use targeted immunotherapy (or biological therapy). With this type of cancer treatment, doctors give patients special medicines that identify ("tag") the cancer cells so that the body's own immune system can find them and fight them off.
What Are the Side Effects of Non-Hodgkin Lymphoma Treatment?
Children treated with chemotherapy or radiation for non-Hodgkin lymphoma usually have side effects. Most are temporary. How severe the side effects are and how long they last can vary based on the child, which medicines are used, and which treatments are given.
The most common short-term side effects of chemo are nausea (medicines can help manage this), vomiting, lower blood counts that can increase the risk of infection or bleeding, or a flu-like feeling. Some kids feel weak or dizzy after their treatments, or run a fever. Others get sores in their mouths or suddenly don't feel much like eating. It's also common for kids to lose some or all of their hair.
The short-term side effects of radiation can be similar, but usually are more localized, meaning they affect only the area that receives the radiation treatment. Kids can continue to feel side effects for weeks after their treatment ends.
Kids who have had non-Hodgkin lymphoma need to keep seeing an oncologist for several years after treatment. Occasionally, cancer may return. Follow-up appointments with a cancer specialist can help doctors treat it early if it does.
Non-Hodgkin lymphoma can be an aggressive disease. The good news is that treatments have improved in recent years. Researchers are constantly developing new and better ways to treat it. Today, most people who have non-Hodgkin lymphoma can be cured.