THE EFFECT OF BCR-ABL(IS) LEVELS ON EARLY AND LATE-STAGE RESPONSE RATES AND PROGNOSIS AT THE TIME OF DIAGNOSIS IN PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) IN CHRONIC PHASE

Vehbi DEMİRCAN, Abdullah KARAKUŞ, Songül BESKİSİZ DÖNEN, Mehmet Orhan AYYILDIZ

Sakarya Tıp Dergisi - 2026;16(3):392-397

Dicle University, Department of Hematology, Diyarbakır, Türkiye

 

Objective: The BCR-ABL(IS) value plays a crucial role in the prognosis of chronic myeloid leukemia (CML) patients. The aim of this study was to compare molecular response rates two BCR-ABL(IS) score levels at the time of diagnosis in chronic-phase CML patients. Methods: The study included 104 patients diagnosed with chronic-phase CML at the Hematology Clinic of Dicle University Faculty of Medicine. BCR-ABL(IS) values were measured during the course of the patients' treatment, with a median follow-up period of 42 months. Molecular response rates were assessed at the 3rd, 6th, and 12th months, and long-term follow-up was conducted to evaluate the effect of BCR-ABL(IS) values at diagnosis on patient outcomes. Results: Patients were divided into two groups based on their BCR-ABL(IS) values at diagnosis: 52 patients (50%) had BCR-ABL(IS) values below 75% (median BCR-ABL(IS) = 56.3%), and 52 patients (50%) had BCR-ABL(IS) values above 75% (median BCR-ABL(IS) = 111%). No significant difference was observed between the early (3rd and 6th months) and late (12th month and long-term) optimal response rates between the two groups. Both groups showed similar responses at these time points, indicating that the initial BCR-ABL(IS) value did not significantly impact the response rates or prognosis at the 3rd, 6th, and 12th months, in the long-term follow-up. Conclusions: The prognosis of CML patients is influenced by various factors at diagnosis, including patient characteristics and disease factors. However, our study found that the BCR-ABL(IS) value at the time of diagnosis is not a predictive factor for prognosis.