The diagnosis, evaluation, and treatment of cutaneous T-cell lymphoma

Cutaneous T-cell lymphomas (CTCL) are rare non-Hodgkin's lymphomas with a dominant T-cell clone. Mycosis fungoides and the Sézary syndrome are the most common forms, with approximately 1000 cases yearly. The median age at onset is 55 years, and the male predominance is 2:1. The etiology of mycosis fungoides is unknown. Infectious, genetic, and environmental sources have been proposed. Mycosis fungoides typically presents as patches or plaques that may progress to tumors over time. The Sézary syndrome is the leukemic variant of CTCL characterized by lymphadenopathy, generalized erythroderma, and severe pruritus. As the severity of involvement increases, spread to extracutaneous sites may occur. Diagnosis relies primarily on skin biopsy with routine histologic evaluation. Presently, there is no cure for CTCL. Current treatment includes topical therapy, phototherapy, radiation therapy, systemic chemotherapy, and immunotherapy. The most reliable predictors of response to therapy are the stage of disease and the presence of extracutaneous involvement.