From the perspective of pro-inflammatory cytokine production, skin lesions in early stage CTCL are dominated with Th1/Tc1 cells, with the production of IFNγ and IL-2, while the lesions in advanced stage CTCL are enriched with the expression of the Th2 cytokines IL-4, IL-5, and IL-10 (6). Here, IL4 is linked to primary cutaneous T-cell non-Hodgkin lymphoma.