CAR T-cell therapy for refractory/relapsed primary breast lymphoma: A retrospective cohort study

Abstract Abstract Background: Patients with primary breast lymphoma (PBL) who are refractory to initial therapy or who relapse after intensive chemotherapy usually have a poor prognosis. Although there has been considerable progress in the use of chimeric antigen receptor-modified (CAR) T-cell immunotherapy for the treatment of relapsed or refractory (r/r) B-cell tumors or hematological malignancies, explicit data on adult patients with r/r PBL are limited. This study aimed to retrospectively analyze the clinical outcomes and treatment courses of 11 patients with PBL who received either CAR T-cell therapy alone or autologous stem cell transplantation (ASCT) combined with CAR T-cell therapy in our center. Methods: We evaluated the clinical efficacy and toxicity of cluster of differentiation (CD) 19 CAR T or sequential CD19/CD22 CAR T-cell immunotherapy, either alone or in combination with ASCT, in 11 adult patients with r/r PBL. Results: Nine patients with diffuse large B-cell lymphoma and two with Burkitt lymphoma were enrolled. In total, eight of the 11 patients with r/r PBL included in our trials responded to the therapy, and seven patients eventually achieved complete response. The overall response and complete remission rates were 72.73% and 63.64%, respectively. After a median follow-up time of 17 months, seven patients ultimately survived. The estimated 1-year overall survival and progression-free survival rates were 63.6% and 61.4%, respectively. None of the patients experienced grade 3–4 cytokine release syndrome and any grade immune effector cell-associated neurotoxicity syndrome. Conclusions: Our preliminary results indicate that a novel therapy with CAR T-cell infusion alone and in combination with ASCT is effective and has relatively manageable side effects in treating patients with r/r PBL.