New perspectives in experimental and clinical research for cutaneous T cell lymphomas.

Cutaneous T cell lymphomas (CTCL) are lymphoproliferative disorders, which can be classified by an adaptation of the Kiel classification. The most common CTCL, Mycosis fungoides (MF) and Sézary syndrome (SS), are monoclonal T helper memory lymphomas. They belong to the group of peripheral T cell lymphomas. However, CTCL includes other disease entities such as granulomatous slack skin, pagetoid reticulosis, and lipotropic CTCL. Polymerase chain reaction of the T cell receptor (TCR)-gamma and screening of the PCR products for sequence-specific mobility in acrylamide gels has increased the detection limit for clonal T cells in the skin. This method will help to define the relationship of CTCL to other lymphoproliferative disorders and may contribute to the early diagnosis of CTCL. In SS, the malignant CTCL clone secretes a T helper-2 cytokine pattern, which might be responsible for the systemic immunosuppression in CTCL patients. New treatment modalities (IL-12) might correct these immunologic abnormalities. Cutaneous B cell lymphomas mostly are follicular center cell derived and usually have a good prognosis. Therapy of cutaneous lymphomas should take into account prognostic factors, the most reliable of which in CTCL is the tumor mass expressed by the tumor burden index.