Differential Expression of Programmed Death-1 (PD-1) in Sézary Syndrome and Mycosis Fungoides

OBJECTIVE To determine if there are differences in the expression of programmed death-1 (PD-1) between SS and MF, and in particular erythrodermic MF (E-MF). PD-1 is a marker of follicular helper T (TFH) cells and is expressed by the neoplastic T cells of some types of malignant T-cell lymphoma, including mycosis fungoides (MF) and Sézary syndrome (SS). Reported results of PD-1 staining in MF and SS are, however, conflicting. DESIGN...