The lymphatic system, an important part of your immune system, is a network of vessels (tubes) and glands (called lymph nodes) that allow waste, toxins and other unwanted substances to leave your organs. White blood cells that fight infections and promote healing circulate throughout the lymphatic system. Lymphoma is a type of cancer that affects the lymphatic system. It arises when white blood cells, called lymphocytes, reproduce rapidly and uncontrollably, for no useful purpose.

There are two primary categories of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma. Together, these account for more than half of all diagnosed blood cancer cases in the United States. Lymphomas are the third most common cancer for children under the age of 14, and the most common cancer for children ages 15 to 19. Though a diagnosis of cancer is never good news, lymphoma is one that can be treated. Effective treatments include chemotherapy, radiation therapy, immunotherapy and other targeted therapies.

Yale medical professionals and support teams are available around the clock to answer questions and provide solutions to issues that arise before, during and following treatment. Our goal is to listen to patients and their families and provide the best care for people with cancer.

Lymphoma is cancer of the lymphatic system, particularly lymph nodes. Lymphoma occurs when abnormal white blood cells, known as lymphocytes, irregularly reproduce and take up space in the body’s lymph nodes, disrupting their normal function. Lymph nodes are located all over your body, including your neck, armpits, groin, chest and abdomen. Because of this, lymphoma can develop anywhere in your body.

There are two primary categories of lymphoma: Hodgkin lymphoma, named after the doctor who discovered the disease, and non-Hodgkin lymphoma, a category that includes over 60 different types of lymphoma.

• Hodgkin lymphoma (HL) is rare, affecting only about 12 percent of people with lymphoma. It rarely spreads to other organs in your body, and is considered to be a very treatable type of lymphoma. Among other features, HL can be identified by the presence of Reed-Sternberg cells, which are large, abnormal lymphocytes that increase in number as disease severity increases.
• Non-Hodgkin lymphoma (NHL) is a category of cancers that affect three types of white blood cells in the lymphatic system: B-lymphocytes (B cells), T-lymphocytes (T cells), and natural killer cells (NK cells). B-cell lymphomas are the most common, representing as much as 85 percent of all NHL. NHL can sometimes spread to other parts of the body including the liver, brain and bone marrow. Slower-progressing NHL is referred to as indolent NHL, while rapidly progressing NHL is referred to as aggressive NHL. 

The risk factors for lymphoma are not fully understood, though it is believed that blood cancers develop from a combination of genetic and environmental factors. In general, lymphoma is more common in men than in women. In the U.S., white men and women are more likely to be affected than other races. Epstein-Barr, HIV, and human T-cell lymphoma/leukemia virus infections are known risk factors for developing lymphoma. Age can also play a role—young adults in their 20s and people over the age of 55 are most likely to develop HL, whereas older adults over the age of 60 are more likely to develop NHL. Additional risk factors for NHL include exposure to certain chemicals (including benzene and chemotherapy drugs), radiation, a weakened immune system, autoimmune disease, and a high-fat diet and/or obesity. 

Symptoms of lymphoma include painless, swollen lymph nodes, fever, chills, night sweats, itchy skin, fatigue, weight loss, and cough or shortness of breath. NHL may present additional symptoms, including pain in the chest, abdomen and bones, a swollen abdomen and the sensation of feeling full even after eating only a small amount. 

Doctors diagnose lymphoma by collecting a medical history, performing a physical exam, and running one or more diagnostic tests.

Your doctor will ask you about your symptoms and whether you have any risk factors for lymphoma. During the physical exam, they will feel your lymph nodes to check for swelling and look for other signs and symptoms indicative of lymphoma.

If your doctor suspects lymphoma, they will order some additional tests, including bloodwork to check for infections and to measure the levels of white blood cells. A biopsy of lymph node tissue is necessary to confirm a lymphoma diagnosis. Doctors may collect this tissue sample via a surgical procedure, as in excisional (removal of an entire lymph node) or incisional (removal of part of a lymph node) biopsy, or by using a needle. After the biopsy, a pathologist examines the tissue sample under a microscope to check for the presence of cancer. Excisional and incisional biopsies are the most commonly used techniques because they ensure that enough tissue is removed for analysis.

Your doctor may also order imaging tests such as a computed tomography (CT) scan, magnetic resonance imaging (MRI) study, positron emission tomography (PET) scan, or ultrasound to locate swollen lymph nodes and determine whether cancer has spread elsewhere in the body.

A bone marrow biopsy may be needed if lymphoma is diagnosed. In this procedure, a needle is inserted and used to remove small samples bone marrow and bone. A pathologist analyzes these samples under a microscope to check if the cancer has spread to the bone marrow. 

Treatments for lymphoma have improved significantly over the last several decades. Treatment for your lymphoma will depend on the type of lymphoma you have, your age, how fast the cancer is progressing, and whether the cancer has spread to other parts of your body. Treatments include the following:

• Chemotherapy refers to anticancer drugs that are given to kill and halt the production of cancer cells. These drugs are often used in various combinations to attack the cancer cells using different mechanisms.

• Radiation therapy kills cancer cells by exposing them to radiation. It is often used to treat early-stage non-Hodgkin lymphoma. For more advanced non-Hodgkin lymphomas, radiation therapy may be given at the same time as chemotherapy. Radiation therapy may be used after or in combination with chemotherapy to treat Hodgkin lymphoma.

• Targeted therapies are drugs that are designed to specifically target cancer cells. Because targeted therapies are directed at cancer cells only, they cause less harm to normal cells than chemotherapy and radiation therapy.

• Hematopoietic stem cell transplantation (also called bone marrow transplantation) refers to healthy blood stem cells that are infused into your body. High doses of chemotherapy kill cancer cells, but it can also harm healthy cells, including blood stem cells that are responsible for producing new blood cells. A stem cell transplantation helps the body recover the capacity to make new blood cells and recover from cancer treatment.  

• Surgery, though rare, is sometimes used to remove affected lymph nodes or organs.

• Immunotherapy is used to stimulate or suppress the patient’s own immune system to fight cancer.

Yale Medicine has a collaborative team of medical professionals who provide patients with comprehensive lymphoma care from diagnosis through treatment, with the goals of comfort and cure.

A typical lymphoma treatment team includes experts trained in both adult or pediatric cancer care who are oncologists, oncology nurses, surgeons, radiologists, pathologists, geneticists, social workers, psychologists, radiation oncologists, pharmacists, child life experts, technicians, complementary care providers and therapists.