However, based on the shared pathogenesis between SPTCL and HLH in the presence of HAVCR2 mutations, immunosuppressive therapy (IST), which is a mainstay treatment for HLH [12], holds potential as a therapeutic approach for patients with SPTCL, especially in younger patients who frequently harbor HAVCR2 mutations and manifest with HLH/HLH-like systemic illnesses [7]. Here, HAVCR2 is linked to hemophagocytic syndrome.