PDFs by language
Our 24/7 cancer helpline provides support for people dealing with cancer. We can connect you with trained cancer information specialists who will answer questions about a cancer diagnosis and provide guidance and a compassionate ear.
Chat live online
Select the Live Chat button at the bottom of the page
At our National Cancer Information Center trained Cancer Information Specialists can answer questions 24 hours a day, every day of the year to empower you with accurate, up-to-date information to help you make educated health decisions. We connect patients, caregivers, and family members with valuable services and resources.
Or ask us how you can get involved and support the fight against cancer. Some of the topics we can assist with include:
For medical questions, we encourage you to review our information with your doctor.
Cancer starts when cells begin to grow out of control. Cells in nearly any part of the body can become cancer, and can spread to other areas. To learn more about how cancers start and spread, see What Is Cancer?
Lymphoma is a cancer that starts in white blood cells called lymphocytes, which are part of the immune system. The main types of lymphomas are:
Lymphocytes are in the lymph nodes (small, bean-sized collections of immune cells throughout the body) and other lymphoid tissues (such as the spleen, bone marrow, and some other organs, including the skin). Lymphomas can start in any of these places.
When a non-Hodgkin lymphoma starts only in the skin (not in other organs or tissues) it is called a skin lymphoma (or cutaneous lymphoma). A lymphoma that starts in lymph nodes or another part of the body and then spreads to the skin is not a skin lymphoma (because it didn’t start there).
Hodgkin lymphoma and other types of non-Hodgkin lymphoma are discussed on separate pages.
To understand what lymphoma is, it helps to know something about the lymph system (also known as the lymphatic system). The lymph system is part of the immune system, which helps fight infections and some other diseases. The lymph system also helps fluids move around the body.
The lymph system is made up mainly of lymphocytes, a type of white blood cell. The main types of lymphocytes are:
Both types of lymphocytes can develop into lymphoma cells. In the skin, T-cell lymphomas are more common than B-cell lymphomas.
Doctors can tell B cells and T cells apart with lab tests that detect certain proteins on their surfaces and certain features of their DNA. These tests also can recognize several stages of B-cell and T-cell development. This can help doctors figure out which type of lymphoma a person has, which can help determine their treatment options.
Most lymphocytes are in lymph nodes, which are bean-sized collections of lymphocytes and other immune system cells throughout the body. Lymph nodes are connected to each other by narrow tubes like blood vessels called lymphatics (or lymph vessels), which carry a colorless, watery fluid (lymph) that contains lymphocytes.
Along with the lymph nodes, lymphocytes can be found in the blood and in lymphoid tissues in many other places in the body, including the:
Lymphomas can start in any part of the body that contains lymph tissue.
Some other types of cancer, such as lung cancer or colon cancer, can spread to lymph tissue such as the lymph nodes. But cancers that start in these places and then spread to the lymph tissue are not lymphomas.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Foss FM, Gibson JF, Edelson RL, Wilson LD. Chapter 104: Cutaneous lymphomas. In: DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2015.
Querfeld C, Rosen ST. Chapter 107: Cutaneous T-cell lymphoma and cutaneous B-cell lymphoma. In: Niederhuber JE, Armitage JO, Dorshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 5th ed. Philadelphia, Pa. Elsevier: 2014.
Last Revised: March 29, 2018
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.