IL1B and synovial sarcoma: Noteworthy, although an increased concentration of IL‐1β and its family members was not constantly found in SS serum and skin specimens [26, 27, 28], their downstream effectors and induced cytokines, including granulocyte‐colony stimulating factor (G‐CSF) and IL‐6 were found in elevated concentrations in peripheral blood of SS patients, especially during the active stages of disease [26, 27, 28, 29, 30, 31].