PB1765: EFFICACY OF A NEW INDUCTION REGIMEN IN THE TREATMENT OF EARLY T-CELL PRECURSOR ACUTE LYMPHOBLASTIC LEUKEMIA.

Abstract

Background: There is no standard induction chenotherapy for adult acute lymphoblastic leukemia. Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has poor response to standard intensive chemotherapy, high risk of recurrence and poor prognosis. Aims: To explore the appropriate induction program to improve the remission rate and prolong the survival period. Methods: A total of 21 newly diagnosed patients with ETP-ALL who received induction chemotherapy with different regimens in the Second Affiliated Hospital of Chongqing Army Military Medical University (Xinqiao Hospital) from January 2017 to December 2020 were retrospectively analyzed for efficacy and main adverse reactions.The initial diagnosis of ETP-ALL was based on the results of bone marrow cytology and flow cytometry immunophenotype. Results: The 21 patients included 14 males and 7 females, with a median age of 27(16-57) years. Among them, 7 patients received PCIOD program and 14 patients received VTLP like program.Among the 7 patients who received PCIOD, 5 patients achieved cytological response (71.43%), and 2 patients were MRD negative (28.57%).In VTLP-like regimen, 7 patients (50%) had cytological remission, of which 1 patient (7.14%) was MRD negative.Major adverse reactions: bone marrow suppression, granulocytopia with fever and septicemia were the major adverse reactions after chemotherapy.Among the 7 patients with PCIOD, 3 patients developed pulmonary infection, including 1 patient with sepsis (klebsiella pneumoniae), while 5 patients with VTLP-like regimen developed pulmonary infection, 3 patients with sepsis, and 2 patients with acute pancreatitis.It did not increase the incidence of major adverse events compared with conventional regimens.There was no treatment-related mortality in any of the patients. Summary/Conclusion: ETP-ALL induced remission rate is low, malignant degree is high, prone to early recurrence and short survival.PCIOD regimen can improve the complete response rate and MRD conversion rate of ETP-ALL patients, and does not increase the treatment-related mortality. However, due to the small number of cases, it needs to be further confirmed by multi-center, randomized controlled studies.