Monitoring the extracorporeal photopheresis by immunophenotyping in a Sézary syndrome patient.

The extracorporeal photopheresis is indicated as immunomodulatory treatment in primary cutaneous T-cell lymphoma. There are no guidelines about the most suitable immunophenotypic panel to monitor and correlate clinical evolution and laboratory parameters. In this study we characterize a patient with Sézary syndrome stage III, who performed 98 sessions of photopheresis; in the last 30, the expression of T-cells in peripheral blood was evaluated. The patient had exfoliative dermatitis (mainly in the lower limbs) and several analytical disorders: anemia, neutropenia and lymphocytosis; abnormal number of effector T-cells and a CD4/CD8 ratio higher than 10; atypical cells (CD7, CD26) with aberrant phenotype (characteristic of malignant T-cell clones); and regulatory T-cells indicating an immunotolerance state. The clinical evolution verified can be related with the therapeutic scheme adopted. We propose a multiparameter flow cytometry approach to monitor patients with Sézary syndrome that realize photopheresis, including the aberrant cases.