Mycosis fungoides and Sézary syndrome are diseases in which lymphocytes (a type of white blood cell) become malignant (cancerous) and affect the skin. Normally, the bone marrow makes blood stem cells (immature cells) that become mature blood stem cells 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 Sézary syndrome, cancerous T-cells are found in the blood. Also, skin all over the body is reddened, itchy, peeling, and painful. There may also be patches, plaques, or tumors on the skin. It is not known if Sézary syndrome is an advanced form of mycosis fungoides or a separate disease.

Signs & Symptoms

A sign of mycosis fungoides is a red rash on the skin. It may go through the following phases:

  • Premycotic phase: A scaly, red rash in areas of the body that usually are not exposed to the sun. This rash does not cause symptoms and may last for months or years. It is hard to diagnose the rash as mycosis fungoides during this phase.
  • Patch phase: Thin, reddened, eczema-like rash.
  • Plaque phase: Small raised bumps (papules) or hardened lesions on the skin, which may be reddened.
  • Tumor phase: Tumors form on the skin. These tumors may develop ulcers and the skin may get infected.

Check with your doctor if you have any of these signs.

Treatment

There are five types of standard treatment. Your OHC doctor will help you determine the best care plan for you.

  • Photodynamic therapy is a cancer treatment that uses a drug and a certain type of laser light to kill cancer cells. A drug that is not active until it is exposed to light is injected into a vein. The drug collects more in cancer cells than in normal cells. For skin cancer, laser light is shined onto the skin and the drug becomes active and kills the cancer cells. Photodynamic therapy causes little damage to healthy tissue. Patients undergoing photodynamic therapy will need to limit the amount of time spent in sunlight.

    In one type of photodynamic therapy, called psoralen and ultraviolet A (PUVA) therapy, the patient receives a drug called psoralen and then ultraviolet radiation is directed to the skin. In another type of photodynamic therapy, called extracorporeal photochemotherapy, the patient is given drugs and then some blood cells are taken from the body, put under a special ultraviolet A light, and put back into the body. Extracorporeal photochemotherapy may be used alone or combined with total skin electron beam (TSEB) radiation therapy.
  • Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
  • Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. The way the chemotherapy is given depends on the type and stage of the cancer being treated.
  • Other drug therapy
  • Biologic therapy, or immunotherapy, is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy. Interferon is a type of biologic therapy used to treat mycosis fungoides and Sézary syndrome. It interferes with the division of cancer cells and can slow tumor growth.