Evaluation of response of clinical and laboratuary parameters in patients diagnosed with CML between 2006 and 2019.

Purpose: Chronic myeloid leukemia (CML) is a hematopoietic stem cell disease characterized by excessive and uncontrolled proliferation of myeloid serial cells. With the development of TKIs targeting the BCR-ABL protein in the pathophysiology of CML, success in the treatment of CML has increased significantly. In the long-term follow-up of these patients, side-effect management of targeted therapy and close monitoring of response profiles have gained importance in determining the prognosis of the disease. Method: Demographic data (age, sex) of 220 patients over the age of 18 who were followed up at the Department of Hematology of Dicle University Faculty of Medicine between January 2006 and May 2019, laboratory parameters at the time of application (hemoglobin, platelet, leukocyte, eosinophil, basophil, BCR-ABL major, BCR-ABL minor values), treatment after diagnosis (Tyrosine Kinase Inhibitors: Imatinib Mesylate, Nilotinib, Dasatinib, Ponatinib) and treatment response rates were retrospectively analyzed according to the information in the hospital records. Results: All of the cases in our study were diagnosed in chronic stage and 50.4% were female and 49.6% were male. The mean age at the time of diagnosis was 44.2 (standard deviation: 16), while the mean age at diagnosis was 44.8 years for women and the mean age at diagnosis for men was 43.7 years. Splenomegaly was detected in 70.3% of the cases. In our study, the majority of patients (96.8%) received 400 mg imatinib treatment in the first line treatment. Of the 214 patients followed, 117 (54.7%) were treated with 400 mg imatinib in the first-line treatment, while 97 (45.3%) patients were changed due to non-response, resistance to treatment and side effects. Of the 200 patients, 166 (83%) had complete hematologic response at 1st month. Molecular response rates were achieved after 400 mg imatinib treatment in 59.6% at 3rd month, 50% at 6th month, 51.2% at 12th month and 57.5% at 24th month. When the major molecular responses of the patients who received a major molecular response at 3 months and not at 24 months were evaluated; Major molecular response was observed in 62.9% of patients who received major molecular response at 3 months, while there was no molecular response in 24 months at 80%. After the diagnosis to the follow-up until May 2019, the mean survival of the patients was 65.7 months (standard deviation 45.7 months). The 5-year survival rate was 90.9%. In our study, when the survival of the patients with and without molecular response at 3, 6 and 12 months was examined, 50.3 (standard deviation: 35.2), 65 (standard deviation: 40.37), 74.6 (standard deviation: 41) months, the mean life expectancy was found. When the mean leukocyte count, hemoglobin value, platelet count, LDH level and uric acid level at the time of diagnosis were evaluated, it was seen that LDH value had an effect on the mean life expectancy and other parameters were not effective. Risk assessment was performed according to the EUTOS risk score. In the scoring, 65.3% of the patients were in the low risk group and 34.7% were in the 'high risk' group. When the mean life expectancy of low and high risk patients was examined according to the EUTOS risk score, the mean life expectancy of the low-risk group was 52.4 (standard deviation: 35) months, while the mean life expectancy of the high-risk group was 51.3 (standard deviation: 27.2) month. According to the EUTOS risk score, 68.8% of the low-risk patients responded to the first-line treatment, while 57.6% of the high-risk patients failed to respond to the first-line treatment in the evaluation of the response rates of first-line treatment to low and high-risk patients, second line treatment was started. Conclusions: LDH and leukocyte levels at the time of diagnosis were associated with survival. While the EUTOS risk score does not differ in terms of mean life expectancy, it is important for predicting the response to treatment. Key words: chronic myeloid leukemia, EUTOS, tyrosine kinase inhibitors