Chimeric Antigen Receptor T-Cell Therapy in T Cell/Histiocyte-Rich Large B-Cell Lymphoma: A Systematic Review and Meta-Analysis.

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is a rare subtype of B-cell non-Hodgkin lymphoma with an aggressive clinical course and poor prognosis in the case of relapsed or refractory (r/r) disease. Recently, anti-CD19 chimeric antigen-receptor (CAR) T-cell therapy has been approved for the treatment of large B-cell lymphoma (LBCL), but subgroup-specific outcomes in these patients have never been reported. Therefore, only limited retrospective data on the safety and efficacy of CAR T-cell therapy in r/r THRLBCL is available. To comprehensively evaluate outcomes of CAR T-cell recipients with r/r THRLBCL, we performed a systematic literature review (SLR) and meta-analysis (MA). The SLR identified seven studies including 157 patients with r/r THRLBCL. Pooled overall response rates and complete remission rates were 48.3% and 30.4%, respectively. Median progression-free survival was 3.4 months, with a 12-month rate of 29.1% and median overall survival was 15.0 months, with a 12-month rate of 57.4%. Low- and high-grade cytokine release syndrome occurred in 68.3% and 4.5% of patients while low- and high-grade immune effector cell-associated neurotoxicity syndrome was seen in 23.1% and 12.9% of the patients. Overall, no unexpected safety signals were identified in r/r THRLBCL patients receiving CAR T-cell therapy but durable responses were only achieved in a subset of patients.