Retrospective evaluation of chronic myeloid leukemia patients in light of current guidelines

Success has increased significantly with imatinib and other tyrosine kinase inhibitors in the treatment of Chronic Myeloid Leukemia. In the long-term follow-up of Chronic Myeloid Leukemia patients; prognostic factors evaluated before treatment, adverse event management of treatments, response evaluations to treatments, and close monitoring of drug resistance mechanisms have gained importance in clinical practice. In this study, we aimed to retrospectively evaluate 113 Chronic Myeloid Leukemia patients, aged 18 and over, who were diagnosed between January 2005 and January 2023 at Trakya University Faculty of Medicine Hematology Clinic and were under clinical follow-up, in accordance with current guidelines. Demographic, clinical, laboratory, genetic and imaging data, prognostic risk scores, treatments applied, treatment response evaluations, adverse events and complications of the patients were obtained in accordance with the information in the hospital records. Of the 113 patients in our study, 68 (60.2%) were male and 45 (39.8%) were female. The median age at diagnosis of the patients was 57.00 (21.00-88.00) years. According to the World Health Organization 2016 criteria, 106 (93.8%) of the patients were diagnosed in the chronic phase, 5 (4.4%) in the accelerated phase and 2 (1.8%) in the blastic phase. It was observed that 95 of the patients (84.1%) had at least one comorbidity, with a median of 3 comorbidities (min-max: 0-11). It has been shown that having more than 3 comorbidities is a risk factor on survival (p:0.03). Imatinib was started as first-line treatment in all patients, it was observed that 47 of 113 patients (41.6%) who were started on first-line treatment were switched from first-line treatment to second-line treatment. It was observed that the need for third-line treatment developed in 28 of 47 patients (59.6%), for whom second-line treatment was initiated, within a median of 12.5 months (2 120 months). A statistically significant difference was detected in terms of survival between patients who achieved an early molecular response at the 3rd month with imatinib and those who did not (p:0.007). The median follow-up period of the patients since diagnosis was 83 (2-213) months. It was observed that 24 patients (21.2%) died for any reason. The mean life expectancy of all patients was calculated as 168.69 months (Standard deviation 7.60) (153.789-183.597; 95% Confidence interval). The median survival time was not reached during the follow-up period. It has been determined that the probability of mortality increases with increasing age at diagnosis, high risk of European Treatment and Outcome Study, high risk of European Treatment and Outcome Study Long Term Survival, increase in basophil count at diagnosis, number of comorbidities >3, lack of major molecular response to imatinib and uncertain status, and switching to 2nd generation tyrosine kinase inhibitor (respectively p:0.000; p:0.055; p:0.009; p:0.008; p:0.003; p:0.004; p:0.001; p:0.046). Increase in age at diagnosis and failure to achieve major molecular response with imatinib were determined as independent risk factors predicting mortality as a result of multivariate statistical analysis (p:0.022; p:0.031, respectively). Achieving a major molecular response with imatinib was found to be a protective factor against mortality compared to not achieving a major molecular response (p:0.028). Keywords: Chronic Myeloid Leukemia, tyrosine kinase inhibitors, survival, mortality, adverse event