Lymphoma

Symptoms and causes

Lymphoma is cancer that affects the lymphatic system. The lymphatic system is made up of organs, glands, tubelike vessels and clusters of cells called lymph nodes. It's part of the body's germ-fighting immune system. Lymphoma can affect lymph nodes, blood, bone marrow, spleen, and other tissues throughout the body, such as in the gastrointestinal system, central nervous system, bones or skin.

Lymphoma gets its name from the kind of cell that makes up the cancer. Lymphoma starts in germ-fighting white blood cells called lymphocytes. There are many types of lymphoma. The main types are:

• Hodgkin lymphoma. This type is characterized by a special kind of cell called the Reed-Sternberg cell. When healthcare professionals look at these cells with a microscope, the cells are larger than healthy cells. The cells often have more than one nucleus. Healthy cells have only one nucleus. Hodgkin lymphoma often is curable.
• Non-Hodgkin lymphoma. Lymphomas that don't have the Reed-Sternberg cell are considered non-Hodgkin lymphomas. Non-Hodgkin lymphoma is more common than Hodgkin lymphoma. The way non-Hodgkin cells look under a microscope varies depending on the type. Whether a non-Hodgkin lymphoma can be cured also depends on the type.

Treatments for lymphomas may include a "watch and wait" approach, chemotherapy, immunotherapy, radiation therapy, targeted therapy, and clinical trials. Treatments also may include CAR-T cell therapy, bone marrow transplant, also called bone marrow stem cell transplant, and treatments for cutaneous lymphomas.

Parts of the immune system

The lymphatic system is part of the body's immune system, which protects against infection and disease. The lymphatic system includes the spleen, thymus, lymph nodes and lymph channels, as well as the tonsils and adenoids.

Symptoms of lymphoma vary depending on the type you have and what part of the body it affects. Early-stage lymphomas may not cause symptoms. When they happen, symptoms of lymphoma may include:

• Swollen lymph nodes, which might feel like a lump under the skin. They happen most often in the neck, armpit and groin.
• Fever.
• Drenching night sweats.
• Fatigue.
• Weight loss without trying.
• Pain in the chest, abdomen or bones.
• Itchy skin.
• Cough.

Lymphoma of the skin, also known as cutaneous lymphoma, can cause symptoms such as:

• A rash, patch or plaque on the skin.
• Itchy skin.
• A change in skin color. This change may be a shade of red, purple or brown depending on your skin color.
• Skin that is peeling and painful.
• A mass, also called a tumor, on the skin.

If lymphoma involves the brain and spinal cord, also called the central nervous system, symptoms may include:

• Confusion.
• Double vision.
• Headaches.
• Hearing loss.
• Nausea.
• Vomiting.
• Weakness in the arms or legs.

Swollen lymph nodes

One of the most common places to find swollen lymph nodes is in the neck. This image shows three swollen lymph nodes below the lower jaw.

It's not clear what causes lymphoma. Cancer happens when cells develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells. In lymphoma, the cancer cells can build up in the lymph nodes, blood, bone marrow, spleen and other tissues throughout the body.

Lymphoma gets its name from the kind of cell that makes up these cancers. These cancers start in germ-fighting white blood cells called lymphocytes.

Factors that can increase the risk of lymphoma include:

• A family history of lymphoma. Having a blood relative, such as a parent or sibling, with lymphoma may increase your risk of lymphoma.
• A weakened immune system or an autoimmune condition. Having a condition that affects the immune system can increase the risk of lymphoma. Conditions may include rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease and others. The immune system also may be weakened after organ transplant.
• Some infections. Some infections have been linked to lymphoma. These infections include human immunodeficiency virus (HIV), Epstein-Barr virus, human T-lymphotropic virus 1 (HTLV-1), Helicobacter pylori (H. pylori), hepatitis C and others.

There is no way to prevent lymphoma.

Complications of lymphoma may include:

• Relapse. Even after successful treatment, lymphoma may come back. This is called a relapse. Sometimes the relapse happens years later. Some people may have multiple relapses.
• Transformation. Some types of slow-growing lymphomas can change into more-aggressive types. These lymphomas often have a worse prognosis and need stronger treatments.