SS is thought to arise from expansions of mature long-lived CD4+CD7- T-cells with a CD45RO+CD27+CD62L+ TCM phenotype accompanied by a consistently high CCR7 mRNA and protein expression, whereas CCR7 expression in the predominantly TEM cells from cutaneous MF lesions is controversial (165, 178–182). This evidence concerns the gene CCR7 and mycosis fungoides.