Cutaneous T-cell lymphoma may be divided into the several subtypes. Mycosis fungoides is the most common form of CTCL and is responsible for half of all cases.A WHO-EORTC classification has been developed.

There is no cure for CTCL, but there are a variety of treatment options available and some CTCL patients are able to live normal lives with this cancer, although symptoms can be debilitating and painful, even in earlier stages. FDA approved treatments include the following:

- (1999) Denileukin diftitox (Ontak)

- (2000) Bexarotene (Targretin) a retinoid

- (2006) Vorinostat (Zolinza) a hydroxymate histone deacetylase (HDAC) inhibitor

- (2009) Romidepsin (Istodax) a cyclic peptide histone deacetylase (HDAC) inhibitor

Histone deacetylase (HDAC) inhibitors are shown to have antiproliferative and cytotoxic properties against CTCL.Other (off label) treatments include:

In 2010, the U.S. Food and Drug Administration granted orphan drug designation for a topical treatment for pruritus in cutaneous T-cell lymphoma to a pharmaceutical company called Elorac.

Traditionally, mycosis fungoides has been divided into three stages: premycotic, mycotic and tumorous. The premycotic stage clinically presents as an erythematous (red), itchy, scaly lesion. Microscopic appearance is non-diagnostic and represented by chronic nonspecific dermatosis associated with psoriasiform changes in epidermis.

In the mycotic stage, infiltrative plaques appear and biopsy shows a polymorphous inflammatory infiltrate in the dermis that contains small numbers of frankly atypical lymphoid cells. These cells may line up individually along the epidermal basal layer. The latter finding if unaccompanied by spongiosis is highly suggestive of mycosis fungoides. In the tumorous stage a dense infiltrate of medium-sized lymphocytes with cerebroid nuclei expands the dermis.

Diagnosis is sometimes difficult because the early phases of the disease often resemble eczema or even psoriasis. As with any serious disease,

it is advisable to pursue the opinion of a medical professional if a case is suspected. Diagnosis is generally accomplished through a skin biopsy. Several biopsies are recommended, to be more certain of the diagnosis. The diagnosis is made through a combination of the clinical picture and examination, and is confirmed by biopsy.

To stage the disease, various tests may be ordered, to assess nodes, blood and internal organs, but most patients present with disease apparently confined to the skin, as patches (flat spots) and plaques (slightly raised or 'wrinkled' spots).

Peripheral smear will often show buttock cells.