A Retrospective Analysis of Autologous Stem Cell Transplantation Outcomes in Adult Philadelphia Chromosome Positive-Acute Lymphoblastic Leukemia

Abstract

Introduction Philadelphia chromosome positivity (Ph + ) is a poor prognostic feature in adult acute lymphoblastic leukemia (ALL). Allogenic hematopoietic stem cell transplantation in first complete remission (CR1) is recommended. There is limited literature on the role of consolidation autologous stem cell transplantation (ASCT). This study was undertaken to assess the potential of consolidation ASCT in CR1 in adults with Ph + ALL. Objectives The aim of this study was to analyze the safety and efficacy of ASCT in CR1 in adults with Ph + ALL. Materials and Methods Adult patients diagnosed with Ph + ALL who underwent ASCT in CR1 after modified ALL-BFM95 protocol from 2015 to 2017 were included. Patients who achieved major molecular response or better were considered for ASCT with cyclophosphamide-total body irradiation regimen and peripheral blood stem cells infused on day 0. Toxicities as per Common Terminology Criteria for Adverse Event v4.0, disease-free survival (DFS), and overall survival (OS) were assessed. Inclusion criteria: Following patients were included—patients aged 18 years and above diagnosed with Ph + ALL; patients receiving BFM-95 induction chemotherapy protocol; patients who achieved CR after induction therapy; nonavailability of human leukocyte antigen match from a matched sibling donor or matched unrelated donor. Exclusion criteria: Patients not willing or unfit for ASCT and patients planned for allogenic hematopoietic stem cell transplantation were excluded. Results Six adult patients with Ph + ALL underwent ASCT in CR1 (median age: 23 [range: 19–36] years, five patients were males [83%]). Imatinib was started at a median of 11 days from the start of induction IA (range: 10–21). Five patients achieved morphological CR after induction 1A and, one patient at the end of induction 1B. The median time to ASCT (from diagnosis) was 8 months (range: 6.4–13). All the six patients had disease relapse and died due to progressive ALL. The median DFS and OS were 19.2 months and 23.3 months, respectively. Conclusion Consolidation ASCT yielded poor outcomes in this study. There was a significant delay from diagnosis to ASCT, which might have impacted the results.