Cutaneous T cell lymphoma, a rare cancer once, a sharp increase in the U.S.

A U.S. study reported an alarming resurgence of CTCL in the United States, a skin cancer considered rare there thirty years. In France, dermatologists made the same observation and suspect a virus to be the cause of the disease.
A disturbing pathology
Cutaneous T cell lymphoma, also called mycosis fungoides, is initially manifested by redness, itching sources, extending gradually to the whole body. This type of cancer is due to abnormal proliferation of T cells in the skin, in contact with the activated dermis and epidermis.

Formerly rare cancer that has seen its incidence tripled in thirty years in the United States according to a U.S. study published in the Archives of Dermatology JAMA (Journal of the American Medical Association).

The authors do not explain this increase but consider this sufficient impact "alarming" to encourage research on cancer, whose origins remain mysterious to implement a prevention policy.

"A viral infection seems to be the cause of the disease, but this is still a hypothesis," said the MPA Dr. Brigitte Dreno, a dermatologist at the University Hospital of Nantes, which states that the sequences retrovirus HTLV-1 DNA were detected in the keratinocytes of the dermis.

A very slow evolution
Tumorigenic little infectious virus and slow acting discovered in the 1980s, HTLV-1 has the characteristic to stimulate the proliferation of T lymphocytes In the case of mycosis fungoides, these cells would accumulate under the skin, attracted by infected keratinocytes to trigger an immune response and, once in contact with the virus antigens, would multiply endlessly.

This viral origin could explain why the disease is more common in people with HIV, including susceptibility to infection is heightened by their immunosuppression.

Mycosis fungoides achieved mainly people over 60 years old, male. The U.S. study reported higher among the black population that does not seem incidence observed in France.

Its evolution is very slow with the initial stage, an average survival of 25 years or even identical to that of the normal population when the disease is diagnosed at an early stage survival. At this stage, the treatments are not aggressive then undertaken and help maintain a good quality of life.

Treatment with ultraviolet
At a later stage, the red plates extend and thicken, and mycosis fungoides is a leukemic form when hyperactivated T cells back into the bloodstream where they adopt a characteristic morphology. This is called Sezary syndrome, "a condition that requires a heavier treatment," said Brigitte Dreno.

PUVA is generally prescribed in the early stages. Coupled with the ingestion of a photosensitizer, this treatment involves exposing the skin to UVA and UVB which immunomodulatory effect on T cells will enable to disable.

At the stage of Sezary syndrome, the hyperactivated lymphocytes having joined the bloodstream, it must then be extracted from the blood and exposed in vitro to the same type of radiation before being reintroduced into the blood. It is extracorporeal photochemotherapy or photopheresis.

"The relapse rate is very high, this lymphoma can be considered incurable," said Dr. Dreno. "These treatments are therefore suspending and preventing the disease to progress to severe stages." Hence the need to diagnose early enough to control the development of lymphoma and confined only to the skin level.

At Nantes University Hospital, doctors are also seeing an increase in cases of mycosis fungoides, which is due, according to the specialist, better screening. The pathology is indeed better known and "people with skin redness tend to consult more quickly." The AIDS epidemic also explain this increase.