Mycosis fungoides is the most common type of cutaneous T-cell lymphoma, a rare form of non-Hodgkin's lymphoma. The cause of mycosis fungoides remains unknown and there is no known cure. Unlike most non-Hodgkin's lymphomas, mycosis fungoides is caused by malignant T-cells.


Mycosis fungoides often presents with an area of red, slightly scaly skin, usually in sun-protected parts of the body, with variable size and shape. Common locations for these symptoms are the buttocks, trunk, upper thighs – all areas that are typically shielded from sun exposure.

MF is very difficult to diagnose in early stages as symptoms and skin biopsy findings are similar to other skin conditions, leading to frequent misdiagnosis. Patients may go on for years before a definitive diagnosis is established.  Both the clinical findings (based on both history and examination) and the skin biopsy findings are essential for diagnosis. Physicians will examine lymph nodes and often order blood tests including a test for Sézary cells in the blood.


Treatment is individualized and specific to each person depending on the symptoms and stage of the disease. For many early-stage patients, skin-directed therapies are effective.  Skin directed therapies include:

  • topical corticosteroids
  • phototherapy (UVB – broad or narrow band; PUVA psoralen medication + ultraviolet A)
  • topical chemotherapy (mechlorethamine [know as nitrogen mustard] and carmustine)
  • bexarotene
  • radiation therapy

A Patient’s Guide for Understanding Cutaneous Lymphoma, 9/2013

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