Mycosis Fungoides and the Sezary Syndrome

Mycosis fungoides and the Sézary syndrome are diseases in which a type of white blood cell called lymphocytes becomes cancerous and affects the skin. Mycosis fungoides and the Sézary syndrome are both types of cutaneous T-cell lymphoma, a form of non-Hodgkin lymphoma.

Normally, the bone marrow makes blood stem cells that mature over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell. A myeloid stem cell becomes a red blood cell, white blood cell, or platelet. A lymphoid stem cell becomes a lymphoblast and then one of three types of lymphocytes – white blood cells:

• B-cell lymphocytes that make antibodies to help fight infection.
• T-cell lymphocytes that help B-lymphocytes make the antibodies that help fight infection.
• Natural killer cells that attack cancer cells and viruses.

In mycosis fungoides, T-cell lymphocytes become cancerous and affect the skin. In the Sézary syndrome, cancerous T-cell lymphocytes affect the skin and are in the blood. Get more information about other types of skin cancer, melanoma, Kaposi sarcoma, and non-Hodgkin lymphoma.

Mycosis Fungoides (Including Sezary Syndrome) Treatment (PDQ®)

Source: National Cancer Institute