IL1B and synovial sarcoma: It has been reported that SS is associated with an imbalance of T helper (Th1)/Th2 cells, but recent studies have demonstrated that Th17 cells, T follicular helper cells, and T follicular regulatory cells also participate in the development of SS.2,3 As a histopathological hallmark of SS, various types of immune cells infiltrate SG tissue and secrete many inflammatory cytokines, such as IL-1β, IFN-γ, and TNF-α, leading to tissue destruction and functional loss of the SG.4