CD4 and synovial sarcoma: The diagnosis criteria established by The International Society of Cutaneous Lymphomas (ISCL) consist of an absolute Sezary count ≥1000/uL or an expanded CD4+ cell count with a CD4/CD8 ratio ≥10 or aberrant loss of one or more pan-T-cell antigens (commonly CD7 and/or CD26 in SS cases), or polymerase chain reaction (PCR) detection of clonal T-cell receptor (TCR) gene rearrangement, or cytogenetic demonstration of an abnormal clone (6,7).