Cutaneous T-cell lymphoma (CTCL) is a class of non-Hodgkin lymphoma, which is a type of cancer of the immune system. Unlike most non-Hodgkin lymphomas (which are generally B-cell-related), CTCL is caused by a mutation of T cells. The cancerous T cells in the body initially migrate to the skin, causing various lesions to appear. These lesions change shape as the disease progresses, typically beginning as what appears to be a rash which can be very itchy and eventually forming plaques and tumors before spreading to other parts of the body. Signs and symptoms
The presentation depends if it is mycosis fungoides or Sézary syndrome, the most common, though not the only types. Among the symptoms for the aforementioned types are:  enlarged lymph nodes, an enlarged liver and spleen, and non-specific dermatitis. Cause
The cause of CTCL is unknown. Diagnosis
A point-based algorithm for the diagnosis for early forms of cutaneous T-cell lymphoma was proposed by the International Society for Cutaneous Lymphomas in 2005. Classification
Cutaneous T-cell lymphoma may be divided into the several subtypes. : 727–740  Mycosis fungoides is the most common form of CTCL and is responsible for half of all cases. A WHO-EORTC classification has been developed. Treatment
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.
Folinic acid, also known as leucovorin, is a medication used to decrease the toxic effects of methotrexate and pyrimethamine. It is also used in combination with 5-fluorouracil to treat colorectal cancer and pancreatic cancer, may be used to treat folate deficiency that results in anemia, and methanol poisoning. It is taken by mouth, injection into a muscle, or injection into a vein.Side effects may include trouble sleeping, allergic reactions, or fever. Use in pregnancy or breastfeeding is generally regarded as safe. When used for anemia it is recommended that pernicious anemia as a cause be ruled out first. Folinic acid is a form of folic acid that does not require activation by dihydrofolate reductase to be useful to the body.Folinic acid was first made in 1945. It is on the World Health Organizations List of Essential Medicines. Medical use
Folinic acid is given following methotrexate as part of a total chemotherapeutic plan, where it may protect against bone marrow suppression or gastrointestinal mucosa inflammation. No apparent effect is seen on pre-existing methotrexate-induced nephrotoxicity. Folinic acid can be taken as a pill (orally) or injected into a vein (intravenously) or muscle (intramuscularly).While not specifically an antidote for methotrexate, folinic acid may also be useful in the treatment of acute methotrexate overdose. Different dosing protocols are used, but folinic acid should be redosed until the methotrexate level is less than 5 x 10−8 M.Additionally, folinic acid is sometimes used to reduce the side effects of methotrexate in rheumatoid arthritis patients.