While IFNγ production was high in the malignant T cells and comparable between CTCL benign T cells and control skin T cells (Figures 1C, D), the production of IL-17A was significantly reduced in CTCL benign CD4 T cells when compared to control skin CD4 T cells (Figures 1C, D). This evidence concerns the gene CD4 and primary cutaneous T-cell non-Hodgkin lymphoma.