Extramedullary relapse of acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation treated by CAR T-cell therapy: a case report

Philadelphia chromosome-positive (Ph-positive) acute leukemia (ALL) accounts for around one quarter of adult cases of ALL and is usually associated with poor prognosis. The patients still encounter a high rate of relapse even after they receive hematopoietic stem cell transplantation (HSCT). HSCT is considered the established therapy and best option for many malignant ALL cases, however, disease relapse remains the main reason of failure. In recent years, chimeric antigen receptor (CAR) T-cell therapy has become a promising treatment for patients with advanced blood cancers. Here, we report a rare case of a Ph-positive ALL patient with extramedullary relapse in her cervix after receiving allogeneic HSCT. Given the unsatisfactory response to chemotherapy, tyrosine kinase inhibitor (TKI) treatment, and HSCT transplantation, she had received CD19+ CAR T-cell therapy 8 months earlier. The following ultrasound check indicated that her cervix relapse went through significant remission with almost undetectable tumor mass. This case strongly supports the efficacy of CAR T-cell therapy on adult ALL with extramedullary relapse.