Chylothorax after chimeric antigen receptor T cell therapy for relapsed and refractory diffuse large B-cell lymphoma: A case report

Rationale: Anti-CD19-targeted chimeric antigen receptor (CAR) T cell therapy is effective in treating relapsed/refractory diffuse large B-cell lymphoma (DLBCL). This therapy is associated with several side effects that can be life-threatening such as cytokine release syndrome (CRS). However, chylothorax associated with CRS after CAR-T therapy has not been reported.Patient concerns: A 23-year-old male diagnosed with DLBCL relapsing after autologous peripheral blood stem cell transplantation was treated with anti-CD19-targeted CAR-T cell therapy. After CAR-T cell transfusion, he developed grade 3 CRS includes fever, dyspnea, tachycardia and hypotension. The symptoms of CRS persisted and chest plain film revealed bilateral pleural effusion.Diagnosis: Chylothorax was confirmed by the pleural effusion analysis that triglyceride level was 1061 mg/dL. Bacterial and fungal culture of pleural fluid reported no pathogen was detected. Cytological examination of pleural effusion revealed no malignant cells.Interventions: The chylothorax resolved after treatment with intravenous administration of tocilizumab.Outcomes: On 30-day follow-up, the patient was in stable clinical condition with complete remission of DLBCL on whole-body positron emission tomography scan.Lessons: We reported a rare case of CAR-T associated chylothorax in a patient with relapsed and refractory DLBCL. Grade 3 CRS with high interleukin-6 level was presented in our patient. The symptoms of CRS were improved with tocilizumab treatment and the chylothorax resolved later on. It is suggested that high interleukin-6 releases might induce chyle leakage resulting from activations of endothelium and coagulation. Our finding highlights the occurrence of chylothorax during the course of CAR-T cell therapy and the importance of proper monitoring and prompt management of this life-threatening side effect.