Comparison of allogeneic hematopoietic stem cell transplantation and TKI combined with chemotherapy for adult philadelphia chromosome positive acute lymphoblastic leukemia: a systematic review and meta‐analysis

Objective This study seeks to clarify whether allogeneic hematopoietic stem cell transplantation (allo‐HSCT) is necessary for adult patients with Philadelphia chromosome‐positive acute lymphoblastic leukemia (Ph+ ALL) in post‐remission based on a comparison with tyrosine kinase inhibitor (TKI) combined with chemotherapy. Methods We searched the Pubmed, Embase, and Web of Science databases and limited the date range for the studies from January 2010 to August 2020. A hazard ratio (HR) with a 95% confidence interval (CI) was employed to assess overall survival (OS) and relapse‐free survival (RFS), and an odds ratio (OR) with a 95% CI was used to evaluate the ratio of non‐relapsed mortality (NRM) and non‐relapsed survival (NRS). All analyses were conducted with Stata software 16.0 and Revman 5.3. Results Fifteen studies, totaling 959 patients, were included in our analysis. Among those patients, 473 underwent allo‐HSCT, and 486 received TKI plus chemotherapy. The pooled results showed no difference in OS between outcomes for patients receiving TKI plus chemotherapy and those treated with allo‐HSCT (HR = 0.76, 95% CI [0.51–1.12], p = 0.16). Patients undergoing allo‐HSCT did better than those receiving TKI plus chemotherapy regarding RFS (HR = 0.48, 95% CI [0.37–0.63], p = 0.00), and NRS (OR = 2.64, 95% CI [1.25–5.57], p = 0.00). The NRM rate of the TKI plus chemotherapy group was significantly lower than the allo‐HSCT group (OR = 2.33, 95% CI [1.51–3.59], p = 0.00). Conclusion TKI combined with chemotherapy can be considered a post‐remission treatment option for adult Ph+ ALL patients who are ineligible for allo‐HSCT. However, more prospective studies with large sample sizes should be carried out in the future.
NRM occurred more frequently in the allo‐HSCT patients than in those undergoing TKI plus chemotherapy. TKI combined with chemotherapy can be considered a post‐remission treatment option for adult Ph+ ALL patients who are ineligible for allo‐HSCT.