Supplementary Material for: Refractory subcutaneous panniculitis-like T-cell lymphoma with hemophagocytic syndrome treated with romidepsin and allogeneic hematopoietic cell transplantation

Introduction: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare subtype of cutaneous T-cell lymphoma (CTCL) that when refractory or complicated by hemophagocytic syndrome (HPS) has a poor prognosis. Romidepsin is a histone deacetylase inhibitor (HDACi), but its efficacy for SPTCL is unknown. The efficacy of allogeneic hematopoietic cell transplantation (allo-HCT) is also unclear. Herein, we report a case of refractory SPTCL with HPS that was successfully treated with romidepsin followed by consolidation with allo-HCT. Case Presentation: A 26-year-old female presented with fever, generalized painful erythema, pancytopenia, and hemophagocytosis. 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET-CT) showed diffuse PET-avid infiltration of the subcutaneous adipose tissue found to be SPTCL via skin biopsy. Her SPTCL was refractory to conventional chemotherapy but complete metabolic response (CMR) was achieved after romidepsin. An allo-HCT was used for consolidation, and she remains in complete remission three years later. Conclusion: Romidepsin with allo-HCT consolidation may be an effective approach for refractory SPTCL..