Adults philadelphia-positive B–acute lymphoblastic leukemia in a moderate health access and quality index Country

Aims: to describe clinical and demographic characteristics, as well as to evaluate response and survival outcomes in Philadelphia positive (Ph+) acute lymphoblastic leukemia (ALL) Ecuadorian adults. Methods: A retrospective, multicenter cohort study in patients aged >15 years diagnosed with Ph+ B-cell ALL was carried out. Diagnosis of B-ALL was established based on 2016 WHO classification and Ph+ mutation was confirmed in all cases. Results: 61 (12.4%) were identified with Ph+ chromosome. 56 were included in the analysis, 33 (58.9%) were male, and median age was 40.5 years [interquartile range (IQR): 25–51; range: 16–85]. 46 (82.1%) subjects were treated with Imatinib. CR was achieved in 30 (53.6%) patients. MRD was reported in 13/41 (31.7%). Only 5/29 eligible patients underwent HSCT. 9 (16.1) died in induction phase, all deaths were attributed to bacterial infections. Relapse was recorded in 7 (12.5%). Median OS for total cohort was 11 months (95% CI 8.1–13.9), with a 5-year OS of 26.8%. Imatinib therapy [HR 0.44 (95% CI 0.19 – 0.98); p=0.046]; Imatinib 800mg dose [HR 0.30 (95% CI 0.11 – 0.83); p=0.020]; Hyper-CVAD protocol [HR 0.44 (95% CI 0.21 – 0.93); p=0.031] were associated to better OS. Conclusion: Response and survival outcomes in Ecuadorian population are poorer compared to high income countries caused by high rate of induction death, low availability of MRD monitoring, lack of standardization of treatment protocols, restricted access to HSCT, and delayed initiation to TKIs therapy.