Non-Hodgkin lymphoma is a group of about 30 different cancers that arise in lymph nodes, lymphatics and blood cells. It is also called non-Hodgkin’s lymphoma, NHL, or lymphoma.
Non-Hodgkin lymphoma begins in the lymph system. The lymph (or lymphatic) system is part of the immune system. It collects and destroys invading organisms such as viruses and abnormal cells. The lymph system protects the body from infection and disease.
The lymph system is a network of tissue, vessels, and fluid (lymph). Lymph nodes are part of the lymphatic system. They filter lymph and store white blood cells (lymphocytes).
Lymph nodes are located in the neck, underarms, chest, abdomen, pelvis, and groin. Lymph tissue also resides in the spleen, thymus gland, tonsils, bone marrow, and digestive system.
Lymphatic tissue is composed mainly of lymphocytes. There are two main types of lymphocytes:
- B cells make proteins called antibodies that kill bacteria or viruses.
- T cells play several different roles in the immune system.
Most cases of non-Hodgkin lymphoma develop from B lymphocytes.
Non-Hodgkin lymphoma starts when a lymphocyte changes into an abnormal cell that begins dividing out of control. These abnormal cells often form masses (tumors) in lymphatic tissue such as lymph nodes.
Because lymph tissue is located throughout the body, NHL can begin almost anywhere and spread to other tissues and organs.
NHL is different from Hodgkin’s disease. Patients with Hodgkin’s disease are generally younger than those with NHL. They also have a specific type of abnormal cell in their cancerous lymph nodes and different symptoms. Treatments also vary.
Some people do not notice any signs or symptoms of non-Hodgkin lymphoma. Instead, the disease may be found during a routine doctor’s exam.
The most common symptom of non-Hodgkin lymphoma is a swollen lymph node. It feels like a painless lump under the skin in the neck, armpit, or groin area.
Other typical symptoms include
- fever for no known reason
- extreme fatigue and weakness
- unexplained weight loss
- drenching night sweats
- a rash or very itchy skin
- pain in the chest, abdomen, or bones.
In most cases, these symptoms are not caused by cancer. However, it is important to see a doctor if you or your child experience any of them.
Diagnosis usually begins with a physical exam. Your doctor will check for swollen lymph nodes and organs throughout your body. The exam will include an evaluation of the abdomen looking for the presence of an enlarged spleen, located on the left upper side of the abdomen. He or she will look for general signs of disease. You will be asked about your health habits and past illnesses and treatments, too.
The following tests may be done to confirm a diagnosis of non-Hodgkin lymphoma:
- Blood tests. Blood will be drawn from your arm. Various tests will examine the numbers and appearance of your blood cells. Some tests measure levels of specific substances released into the blood by organs and tissues.
- Lymph node biopsy. All or part of a lymph node will be removed for examination. The lymph node may be removed with a needle or by cutting through the skin or by locating the lymph node with the help of a CT scan and then performing a biopsy under CT guidance.
- Imaging tests. Imaging tests may be used to look for masses. They include
- x-rays, which use high-energy radiation to take pictures inside the body
- computed tomography (CT) scan, which uses a rotating x-ray camera to produce detailed cross-sectional images
- magnetic resonance imaging (MRI), a procedure that uses radio waves and strong magnets to produce detailed pictures
- positron emission tomography (PET) scan, in which radioactive glucose (sugar) is injected into the patient’s vein. A rotating scanner highlights areas where cells are using the glucose. Cancer cells use more glucose than normal cells.
- Laparoscopic biopsy or laparotomy. These are surgeries to look inside the abdomen for disease. Tissue may be removed.
- Bone marrow aspiration and biopsy. A needle is used to take a sample of bone and liquid bone marrow from the hipbone or breastbone. The samples are analyzed for signs of cancer.
- Lumbar puncture (spinal tap). A doctor removes fluid from the lower back with a needle. This test indicates whether there are lymphoma cells in the brain and spinal cord.
- Immunophenotyping. This technique analyzes certain substances on cell surfaces. It can determine whether the patient’s cancerous cells are B or T lymphocytes.
- Cytogenetic analysis. Scientists examine lymphoma cells for changes to their genetic material.
These tests may also be used to determine the type of NHL, how far the cancer has spread, and how fast the cancer is growing.
Have your biopsy sample reviewed and assessed by a specialist who is an expert in lymphomas. This way, you will be offered the best treatment choices for your condition.
In order to select a treatment plan, your doctor will need to determine how far your cancer has spread. This is known as "staging." The four stages of non-Hodgkin lymphoma are
Stage I: Lymphoma cells remain confined to one lymph node group, such as the neck or groin. Or, they are found in part of a single organ or area outside the lymph system.
Stage II: Cancer is in two or more lymph node groups on the same side of the diaphragm. (The diaphragm is the thin muscle separating the chest and abdomen.) Or, the cancer may be in an organ or area outside the lymph system and in lymph nodes near that organ or area. Lymphoma cells may also be in other lymph nodes, still on the same side of the diaphragm
Stage III: Lymphoma cells are in lymph node groups both above and below the diaphragm. Cancer may also have extended into part of an organ or area outside the lymph system and/or the spleen.
Stage IV: The cancer appears throughout one or more organs outside the lymph system. It may be in nearby or distant lymph nodes. In this stage, the cancer cells may be in the liver, blood, or bone marrow.
Recurrent or relapsing non-Hodgkin lymphoma is disease that returns after treatment.
The four numerical stages of non-Hodgkin lymphoma are often further described with the letters A, B, E or S.
A: The patient does not have weight loss, unexplained fevers, or drenching night sweats.
B: The patient has weight loss, unexplained fevers, or drenching night sweats.
E: Lymphoma cells appear in organs outside of the lymph system, such as the lungs or liver.
S: Lymphoma cells are found in the spleen.
Patients also are often given a risk score (ranging from low to high) based on indicators such as age and disease stage.
Additional factors help classify non-Hodgkin lymphoma. These factors affect your chance of recovery. And they may help your doctor to plan a course of treatment. Factors include the following characteristics of lymphoma cells:
- size (large or small)
- shape (with or without folds or indentations)
- pattern (scattered or grouped together).
In addition, non-Hodgkin lymphomas are often classified by their growth rate. Slow-growing NHL cases are also known as indolent or low-grade lymphomas. They may not require treatment beyond "watchful waiting" for some time. Fast-growing lymphomas are also called aggressive, intermediate-grade, or high-grade NHL. These can quickly become life-threatening if not properly treated.
Additional information is obtained by looking at whether specific genetic abnormalities are present. If present, different therapies may be given. More recent studies also determine in which part of the lymph node the lymphoma cells arose from and this is also used in helping determine treatments.
Some forms of non-Hodgkin lymphoma are slow-growing. Treatment may be postponed until symptoms appear. More aggressive forms of NHL require immediate treatment.
Risk factors increase your chance of developing a disease. However, most people who get non-Hodgkin lymphoma don’t have any known risk factors. There is no known way to prevent the illness.
Risk factors for NHL include
- being infected with certain viruses, such as HIV, Epstein-Barr, and hepatitis C
- a history of infection with H. pylori, a bacterium linked with stomach ulcers
- having a weakened immune system due to an organ transplant, inherited condition, or other cause
- having an autoimmune disease
- being older than 60
- having been exposed to certain chemicals
- having been exposed to chemotherapy to treat other cancers
- having been exposed to high doses of radiation
- having certain genetic changes, or mutations.
Standard treatments for non-Hodgkin lymphoma are chemotherapy, radiation therapy, and biologic therapy. They are sometimes used in combination. Doctors may recommend watchful waiting for some patients, particularly those with slow-growing NHL.
Significant advances have been made in the care of patients with NHL. Many new treatments have been developed to specifically attack abnormalities on the lymphoma cells. The results have been promising.
Chemotherapy uses drugs to stop the growth of cancer cells. Chemotherapy drugs are usually taken by mouth or injected into a vein or muscle. They may also be placed directly into the spinal column to treat NHL in the central nervous system.
Chemotherapy regimens often involve several anticancer drugs given in cycles. This means you have a treatment followed by a period of rest. Steroid drugs may be given to relieve swelling and inflammation.
Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells and shrink tumors. It is often combined with chemotherapy.
Radiation for NHL is usually delivered from a machine outside the body. This is known as external beam radiation. But it may also be delivered inside the body, into or near the cancer.
Biologic therapy (immunotherapy)
Immunotherapy taps the body’s immune system to kill cancer cells or limit their growth. One biologic therapy is monoclonal antibodies. Monoclonal antibodies are laboratory-made antibodies. Antibodies are proteins that respond to substances that provoke the body’s immune response.
Monoclonal antibodies are injected into the bloodstream. They may be used alone or to transport drugs, toxins, or radioactive material to cancer cells.
Stem cell transplant
Stem cell transplants are used to rebuild the patient’s blood-forming cells. This may be necessary if the cells are abnormal or have been damaged by cancer treatment.
Stem cell transplants can use stem cells (immature blood-forming cells) from the patient’s body or from a donor’s. After the stem cells are collected, they are frozen and stored.
The patient receives high-dose chemotherapy and/or radiation therapy. This kills the diseased cells. But it also damages or destroys the bone marrow. The stored stem cells are thawed and infused back into the bloodstream. They travel to the bone marrow and begin producing new blood cells.
Watchful waiting means that treatment is avoided until the patient begins to show symptoms. This may be appropriate for some patients with slow-growing, or indolent, lymphoma. Regular, careful monitoring is an important component of watchful waiting.
For pregnant women, treatment is chosen carefully to minimize its effects on the fetus.
Side effects and supportive therapy
Many treatments for non-Hodgkin lymphoma have short- and long-term side effects. Common short-term side effects include
- mouth sores
- hair loss
- low blood cell counts that can increase the risk of fever and infection
Your doctor may be able to lessen these symptoms. Some ways to do this include having blood transfusions and taking growth factors or antibiotics.
The possible long-term side effects of treatment are:
- fertility problems
- heart damage
- increased risk of developing a second cancer in the future including leukemia.
New medical approaches are being tested through clinical trials. You may want to consider joining a clinical trial if there is one that fits your medical and personal situation.
When To Call a Professional
Contact your doctor if you experience symptoms of non-Hodgkin lymphoma, including
- swollen lymph nodes
- unexplained fever
- extreme fatigue and weakness
- unexplained weight loss
- drenching night sweat
- extremely itchy skin or rash
- pain in the chest, abdomen, or bones.
The outlook for patients with non-Hodgkin lymphoma depends on several factors:
- the type of NHL
- the cancer’s stage
- the patient’s age and general health
- whether the lymphoma is newly diagnosed or has come back.
Prognosis also depends on the blood level of LDH. This is an enzyme that increases in the presence of fast-growing tumors.