Long-Term Treatment Outcomes and Prognostic Factors in Patients with Chronic Myeloid Leukemia: A 24-Year Single-Center Retrospective Study

Background and Objectives: Chronic myeloid leukemia (CML) outcomes have markedly improved with tyrosine kinase inhibitor (TKI) therapy, but long-term real-world data on treatment patterns and prognostic scores from middle-income settings remain limited. This study evaluated treatment patterns, reasons for TKI switching, response rates, the performance of established risk scores, and factors associated with 10-year overall survival (OS) in patients with CML followed at a tertiary center over 24 years. Materials and Methods: This single-center, retrospective study included 178 adult patients with CML followed at the Department of Hematology, Çukurova University Faculty of Medicine, between 2000 and 2024. The Sokal, Hasford, EUTOS, and EUTOS long-term survival (ELTS) scores were calculated with age at diagnosis. OS was estimated by the Kaplan–Meier method, and factors associated with 10-year OS were assessed by Cox regression. Results: The median age at diagnosis was 47 years, and 87.6% of patients were in chronic phase. Imatinib was used as first-line therapy in 99.4% of patients; 104 patients (58.4%) required at least one TKI switch, most commonly because of resistance. Major cytogenetic, major molecular, and deep molecular responses were achieved in 88.4%, 76.7%, and 53.2% of patients, respectively. With a median follow-up of 10.7 years, 10-year OS was 80.7% (95% confidence interval [CI] 72.6–86.6) overall, 88.6% in chronic phase, and 13.6% in accelerated/blastic phase. In multivariable analysis, accelerated/blastic phase (hazard ratio [HR] 5.75, 95% CI 2.58–12.79) and older age at diagnosis (HR 2.09 per 10 years, 95% CI 1.54–2.82) were independently associated with mortality. In chronic-phase patients, the ELTS score showed the best discrimination (C-index 0.90, versus 0.88 for Sokal and 0.78 for Hasford), with 10-year OS of 96.4%, 71.4%, and 12.5% in the low-, intermediate-, and high-risk groups, respectively. Conclusions: In this long-term real-world cohort, imatinib-based sequential TKI therapy achieved high response rates and favorable long-term survival in chronic-phase CML. Disease phase and age at diagnosis were the main determinants of survival, and the ELTS score was the most informative baseline risk score in chronic-phase patients.