Due to the limited evidence supporting a role for CCR1, CCR2, CCR3, CCR5, CCR6, CXCR1, CXCR2, CXCR5, and CX3CR1 in the pathogenesis or progression of MF and SS, their physiological functions will be briefly summarized. The gene discussed is CXCR5; the disease is synovial sarcoma.