Complications of therapeutic plasma exchange: A retrospective, single-center study of 2505 procedures performed in 338 patients over 15 years.

INTRODUCTION: Therapeutic plasma exchange (TPE) may involve complications. We aimed to review the demographic data, indications, technical information, and complications. METHODS: Data for TPE procedures (TPEPs) performed between 2004 and 2018 were retrospectively. RESULTS: This study covered 2505 TPEPs performed on 338 patients; 55% of them were female (n = 186), and the median age was 36 years (range, 11-93 years). Most TPEPs were administered for hematological (40.6%) indications. The incidence of complications on the first procedure was 3.2% (n = 80); only 16 procedures (0.6%) were failed. The complication incidence was 19.8% (n = 497), with 789 total complications. Most of the complications were patient-related (90.4%), and the most of them were urticaria (29.1%), occlusion (3.2%), and faulty systems (1.01%), respectively. The use of only fresh frozen plasma as replacement fluid caused a higher complication rate (22.1%, p < 0.01). CONCLUSION: The number of TPEPs is increasing every day. Hematologic indications for TPE and the use of fresh frozen plasma may increase the risk of complications.

Effect of Tyrosine Kinase Inhibitor Therapy on Estimated Glomerular Filtration Rate in Patients with Chronic Myeloid Leukemia.

INTRODUCTION: The advent of tyrosine kinase inhibitors (TKIs) was revolutionary in the management of chronic myeloid leukemia (CML). Although TKIs were generally considered to be safe, they can be associated with renal injury. We evaluated the effect of TKIs on renal functions in a cohort of patients with long-term follow-up. MATERIAL AND METHODS: We retrospectively examined patients with chronic phase CML treated with TKIs. We analyzed the estimated glomerular filtration rate (eGFR) of patients from the initiation of TKI to the last follow-up. eGFR values of CML patients were compared to those of patients with stage 1 or 2 chronic kidney disease (CKD). RESULTS: A total of 195 patients with CML and 138 patients with CKD were examined. eGFR decline was 1.556 ml/min/1.73m2/year for patients with CML (P = .221). Patients receiving second-generation TKIs (2GTKI) were estimated to have 0.583 ml/min/1.73m2 higher eGFR value than that of the imatinib group, but it was not significant (P = .871). eGFR of patients who had used bosutinib had a downward trend. Duration of TKI therapy, age, and hypertension were found to be significant factors in eGFR decline for CML patients. Lower baseline GFR was associated with an increased risk of CKD development. CONCLUSION: Imatinib could result in a decline in eGFR which was clinically similar to early-stage CKD patients. We did not observe significant kidney function deterioration in patients receiving 2GTKIs including dasatinib and nilotinib. We recommend close renal function monitoring in patients receiving imatinib, especially for elderly patients with lower baseline eGFR and hypertension.

Does discontinuing bleomycin due to toxicity increase the risk of lymphoma progression? Real-life data from a homogeneous population of advanced stage Hodgkin lymphoma.

Hodgkin Lymphoma (HL) is often curable with ABVD therapy and improving outcomes is a main goal of ongoing research. Bleomycin-associated pneumonitis (BAPT) is a potentially life-threatening complication that necessitates bleomycin discontinuation. We conducted this study on a homogenous cohort of advanced stage HL treated only with ABVD for frontline therapy to assess if bleomycin discontinuation increases the risk of lymphoma progression. After the exclusion of patients who received radiotherapy or other drugs, 106 and 28 patients in the six-cycle ABVD and BAPT groups respectively had similar survival curves for progression and death with a 49-month median follow-up. PFS rates were also very similar at two and four years from diagnosis with 2-year PFS rates of 83.9% and 82.1% (RR = 1.1 95%CI = 0.45-2.2). Outcome comparisons were also similar between the two groups when stratified according to early response assessment with PET/CT. Patients who discontinued bleomycin due to toxicity did not experience an increased risk of progression compared to patients who completed six ABVD cycles.

Relapsed refractory multiple myeloma with CNS involvement successfully treated with Elranatamab: first reported case.

Central nervous system (CNS) involvement in multiple myeloma (MM) is a rare and challenging complication associated with poor prognosis and limited treatment options. Emerging T-cell directing therapies, such as bispecific antibodies (bsAbs) and chimeric antigen receptor T cells (CAR-T), have shown remarkable success in treating MM, but their efficacy in CNS involvement remains unclear. Elranatamab, a humanized bispecific antibody targeting B-cell maturation antigen (BCMA) and CD3-expressing T cells, has demonstrated promising results in relapsed refractory MM. However, its efficacy in treating CNS-MM has not been reported. We present a case of a 37-year-old male MM patient with CNS involvement who has been successfully treated with Elranatamab.

A cross-sectional study on restless legs syndrome (RLS) in polycythemia vera (PV): is iron deficiency the only culprit?

INTRODUCTION: In polycythemia vera (PV) patients undergoing phlebotomy, iron deficiency (ID) may develop. ID has been linked to restless legs syndrome (RLS), and in one study, 29.6% of PV patients had RLS. We aimed to evaluate the frequency of RLS in PV and to evaluate factors that might play a role in RLS development among PV and essential thrombocythemia (ET) patients. METHODS: We consecutively included PV cases as the patient group, and ET and ID patients and healthy subjects (HSs) were included as controls. Those with conditions that could lead to RLS were excluded. All subjects were questioned according to the diagnostic criteria of the International Restless Legs Syndrome Study Group. RESULTS: Twenty-seven PV, 23 ET, and 22 ID patients and 23 HSs were included. RLS was detected in 25.9%, 34.8%, and 45.5% of PV, ET, and ID patients, respectively. None of the HSs had RLS. In univariate analysis, interferon-α and anagrelide use, magnesium levels, and the Leeds assessment of neuropathic symptoms and signs (LANSS) scores had a significant impact on RLS in PV and ET patients (p = 0.014, p = 0.032, p = 0.036, and p = 0.003, respectively). CONCLUSION: RLS was more common among PV and ET patients than HSs, which was irrespective to the iron status. RLS was more frequent in ET patients than that observed in PV cases, indicating that ID may not be the only causative factor for RLS development in PV. Further prospective studies are needed to determine the prevalence and risk factors of RLS developing in PV and ET.

Short-Term Clinical Outcomes of Packed Red Blood Cell Transfusions with Isolated Enzyme-Phase Crossmatch Incompatibility: A Single-Center Cross-Sectional Study

Acute hemolytic transfusion reactions (AHTRs) are feared complications of packed red blood cell (PRBC) transfusions. This study aimed to investigate the clinical consequences of isolated enzyme-phase crossmatch-incompatible PRBC transfusions by clinically observing all events during the study period at a single institution with the primary goal of detecting AHTRs. Ninety-four transfusions of interest were administered during the study period. Laboratory investigations were adequate in 73 episodes, where no AHTR developed and a mean hemoglobin concentration rise of 1.1 g/dL was documented. Three transfusions were terminated prematurely; however, further investigations ruled out AHTR. The remaining 21 transfusions were also completed uneventfully without noteworthy clinical deterioration. This study's results provide clinical validation to omit pretransfusion screening with enzyme-phase crossmatch and document the safety and short-term efficacy of isolated enzyme-phase incompatible transfusions. The findings may encourage future clinical research to better understand the long-term efficacy of such transfusions, which may be valuable for transfusion-dependent patients.

Diagnosis and Management of Classical Hodgkin Lymphoma During the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has brought life to a standstill globally. Intermittent quarantines were applied to control the pandemic and reduce contamination. During the pandemic, patients with hematological malignancies were among the most vulnerable population. Our aim was to compare in terms of demographic data, disease-related factors, symptom-to-diagnosis interval, diagnosis-to-treatment interval , and interim and end-of-treatment response in classical Hodgkin lymphoma patients diagnosed during the pandemic and in the pre-pandemic periods. A total of 90 patients were included, of which 65 and 25 were diagnosed in the 2 years before the pandemic and the 12-month period during the pandemic, respectively. Demographic features were comparable in both groups. Although the percentage of patients with advanced-stage disease was higher during the pandemic (64% vs 53.8%), this difference did not reach statistical significance (P = 0.384). The median symptom-to-diagnosis interval was significantly longer during the pandemic than was observed within the pre-pandemic era (16 weeks vs 8 weeks, P = 0.042). The median diagnosis-to-treatment intervals was similar in both groups (13 days vs 15 days, P = 0.253). In the pre-pandemic and pandemic periods, 85.2% and 72.7% of the patients had complete response at end-of-treatment evaluation, respectively (P = 0.208). We found that symptom-to-diagnosis interval was significantly prolonged during the pandemic. Higher percentage of patients with advanced-stage disease during the pandemic might also be due to this delay, nevertheless, this difference did not reach to a significant difference regarding treatment response in both groups.

Treatment Responses, Toxicity, and Survival in Patients with Classical Hodgkin Lymphoma Aged ≥50 Years: A Single-Center Experience Over Two Decades.

Introduction: The aim of this study was to evaluate treatment responses, toxicity, and survival among cHL patients aged ≥50 years. Methods: We retrospectively identified all newly diagnosed cHL patients and only included cases who were ≥50 years old at the time of diagnosis and with data available between 1999 and 2020. Results: There were 101 patients, of which 52 were between 50 and 59 years of age, and 49 patients were ≥60 years old. Sixty-two patients were male, and the most common histopathological subtype was mixed cellularity cHL (58.4%). ECOG PS, CCI, CIRS, and ACE-27 scores were significantly higher in patients aged ≥60 years than those of 50-59 age group. While all patients aged 50-59 years received ABVD as first-line therapy, 79% (n=39) of cases aged ≥60 years had ABVD. In patients receiving ABVD, 95% and 92.7% of the cases aged 50-59 and ≥60 years had CR, respectively (p=0.999). Age groups were comparable in terms of hematological and non-hematological toxicities (p=0.369, p=0.127, respectively). Although not statistically significant, median survival was longer in patients receiving a transplant than in those without transplantation (108 months vs 52 months, p=0.069). In multivariate analysis, the risk of progression was higher in patients with lymphocyte ≤600/mm3 and in those who were unresponsive to first-line therapy (p=0.002 and p<0.001, respectively). Patients with B symptoms, age ≥60 years, and CIRS >3 had higher risk of mortality (p=0.001, p=0.012, p=0.038, respectively). By using these 3 parameters, we defined a new risk score, which divided our patient cohort into two as low- and high-risk groups. Low-risk patients had significantly higher survival rates than the high-risk group (83.9% vs 40.5%, p<0.001). Discussion: This new prognostic score should be further tested and validated in other patient populations. Although our study has some limitations including the limited number of patients and its retrospective nature, there are not so many studies in elderly cHL patients and elderly and/or frail patients are generally excluded in most of the clinical trials. Thus, this real-life single-center experience would contribute to the literature.

Cytogenetic profile of adult AML patients in Turkey: a single center study with comprehensive comparison with literature.

Background: Cytogenetic findings are important prognostic factors in acute myeloid leukemia. Large systematic data about chromosomal characteristics of Turkish AML patients have not been reported to date. Objectives: The karyotypic profiles of 157 adult AML patients were evaluated retrospectively and compared with other reports from different populations. Methods: Cytogenetics analyses were performed on bone marrow samples using G-banding. Patients were categorized according to their cytogenetic results into four groups with the addition of a normal karyotyped group to the favorable, intermediate and adverse groups of European Leukemia Network. Results: Cytogenetic analyses were carried out successfully in 138 patients (88%). Abnormal karyotypes were found in 79 (57.2%) patients of which 13 (9.4%) were in favorable, 37 (26.8%) in intermediate and 29 (21%) in adverse groups. t(8;21) (5%) was the most common favorable abnormality while monosomal karyotypes (15.9%) in adverse group. Conclusion: This single center study is the most comprehensive study about the cytogenetic profile of acute myeloid leukemia in Turkey with comparison of other population-based studies. While there were similarities and differences with different publications, our results did not show a marked tendency to the findings of any specific geographic region.

Candida esophagitis incidentally detected by 18F-FDG PET/CT in a patient with CNS lymphoma.

Corticosteroids are commonly used in lymphoma patients, and findings in favor of esophageal involvement in 18F-FDG PET-CT should be considered suspicious and definitely be confirmed by biopsy. We describe a 58-year-old lady with diffuse large B-cell lymphoma and central nervous system involvement having an increased metabolism in the distal esophagus with 18F-FDG PET/CT, which was consistent with esophageal candidiasis, most probably due to prolonged use of dexamethasone. Esophageal candidiasis can be misdiagnosed as malignancy with a high SUVmax and may lead to difficulties while managing these patients.

Efficacy and Safety of Imatinib Treatment in Elderly Patients With Chronic Myeloid Leukemia: Real-Life Data and a Single-Center Experience.

BACKGROUND: In the era of tyrosine kinase inhibitors (TKIs), chronic myeloid leukemia (CML) patients generally live close to a normal lifespan, and the number of elderly patients with CML with comorbidities is increasing. PATIENTS AND METHODS: We retrospectively compared the efficacy and safety of frontline imatinib between elderly patients (≥60 years old) and younger patients (<60 years old) with CML. RESULTS: The study included 33 elderly and 125 younger patients. Elderly patients had significantly higher Charlson comorbidity index (CCI) scores. Efficacy and toxicity were comparable among the older patients with CCI scores of 0 and ≥1. There were significantly more hematologic adverse events (AEs) in elderly patients (P = .005). Although not significant, nonhematologic AEs were also more common in older cases (P = .056). Elderly patients had significantly higher rates of imatinib dose reduction (P < .001). Cumulative response rates were similar in both groups. Event-free survival was comparable, and overall survival (OS)-when non-CML-related deaths were censored-was also similar. In the multivariate analysis, age at diagnosis and CCI were associated with OS, and patients ≥ 60 years of age had a 5.998-times higher risk of death compared with the patients < 60 years of age (P = .011). Similarly, patients with CCI scores ≥ 2 had a 3.758-times higher risk of death compared with patients with a CCI score of 0 (P = .033). CONCLUSIONS: Upfront imatinib was generally well tolerated among elderly Turkish patients with CML with non-inferior responses and long-term outcomes when compared with younger patients. Comorbidities can be problematic in elderly patients, and today the survival of patients with CML is determined mostly by comorbidities.

The prognostic value of serum levels of a proliferation-inducing ligand (APRIL) in treatment-naïve patients with chronic lymphocytic leukemia

Background/aim: A proliferation-inducing ligand (APRIL) has been investigated as a prognostic marker in chronic lymphocytic leukemia (CLL) patients. However, there is no cut-off level for serum APRIL (sAPRIL) levels that predict time to treatment in CLL patients. Materials and methods: Between May and December 2012, 94 consecutive CLL patients and 25 healthy controls were assessed. sAPRIL levels were measured by ELISA. Demographic data and prognostic markers were obtained from the patients' files. Treatment-naïve patients were followed up for 6.5 years for any treatment need. Results: Patients were divided into 3 groups: Treatment-naïve (n = 47), chemotherapy receiving (n = 25), and those who had received chemotherapy previously (n = 22). There was no difference in median sAPRIL levels of patients who were receiving chemotherapy at the sampling time and the healthy controls, which indicates that sAPRIL levels might be influenced by treatment. For treatment-naïve patients, the best cut-off in predicting time to treatment was found at the sAPRIL level of 2.04 ng/mL, with 78% sensitivity and 63% specificity. Time to treatment was significantly earlier in the APRIL high group (n = 27) than in the APRIL low group (n = 20) (P = 0.010, log-rank test). Conclusion: sAPRIL, a simple, promising blood test which can be measured by ELISA, will likely obtain a place in the wide range of prognostic markers in CLL. Prospective large-scale studies are required to validate and confirm the feasibility of the proposed cut-off level of 2.04 ng/mL as a predictor of time to treatment in treatment-naïve CLL patients.

Copy-number variations in adult patients with chronic immune thrombocytopenia.

OBJECTIVES: Immune thrombocytopenia (ITP) is an autoimmune disease with heterogeneous background. FCGR2C mutations were defined in one third of the patients but genetic players have not been fully elucidated yet. Although childhood ITP present as benign, ITP in adulthood is chronic disease with treatment challenges. This study aimed to focus on adult ITP patients using a whole genome genotyping that is valuable approach to identify the responsible genomic regions for the disease. METHODS: Herein 24 adult primary-refractory for ITP patients were evaluated using HumanCytoSNP12BeadChip,Illumina. Forty-six age and sex matched healthy individuals, and ptients awith nonhematological conditions were analyzed as controls. Identified CNV regions were verified by qRTPCR. T-cell receptor beta and delta (TCRB/TCRG) clonality were assessed by heteroduplex analysis in mosaic cases. RESULTS: Several CNV losses and gains were defined (losses:2q,7q,17q,19p, and gains: 1q,2p,3q,4q,7q,10q,12p,13q,14q,15q,17p,20q,21p,22q,Xp). Mosaic changes of different sizes (0.2-17.77Mb) were identified in five patients and three of them showed clonality. CNV regions that were unique to ITP patients were identified for the first time and among these genes, those related to immune regulation, and cellular trafficking were noteworthy. Conclusion: Identified CNV regions harbor several candidate genes, the functions of which might shed light on the pathogenesis of chronic ITP.

Hepatitis B reactivation in hematopoietic stem cell transplanted patients: 20 years of experience of a single center from a middle endemic country.

Hematopoietic stem cell transplantation (HSCT) is a risk factor for viral hepatitis reactivations because it affects lymphocyte number and functions. Latent hepatitis B virus (HBV) may stay in dormant form in hepatocytes and may be reactivated in prolonged immunosuppression. This study analyzes the incidence of reactivation of HBV infections in HSCT patients in a middle endemic country like Turkey. Five hundred and sixty-one HSCT patients from 1994 to 2015 were retrospectively evaluated. Sixty-six patients had a serologic feature of HBV infection. Fifteen patients were hepatitis B surface antigen (HBsAg)-positive patients (3 allogeneic and 12 autologous) while 51 of them were anti-hepatitis B core IgG (anti-HBc IgG)-positive patients (22 allogeneic and 29 autologous). Although under lamivudine prophylaxis, reactivation was seen in three of 12 (25%) chronic HBV (HBsAg positive) patients who received autologous HSCT and in two of the three HBsAg-positive patients who received allogeneic HSCT. Rate of reactivation in the whole HBsAg-positive group was 33%. Reactivation occurred on median 270th day (range: 60-730). Reverse seroconversion incidence was 10% on 133th day for HBsAg negative, but anti-HBc IgG-positive patients, which increased to 17% on 360th and to 23% on 1500th day. Cumulative incidence increased to 41% on 2280th day for isolated anti-HBc IgG-positive patients. Hepatitis B surface antibodies (anti-HBs) were found to be protective as reactivation did not exceed 11% on 5050th day when anti-HBs was positive. When anti-HBc IgG-positive cases were analyzed according to their transplantation types, allogeneic HSCT was found to have higher cumulative incidence (45% on 3258th day) for HBV reactivation than autologous HSCT (7% on 5050th day). Besides, HBV reactivation in anti-HBc IgG-positive patients who received allogeneic transplantation was related to mortality. Findings of this study suggest that HBV prophylaxis extending over 1 year should be prescribed for HBsAg-positive patients independent of the transplantation type. Prophylaxis should also be given to anti-HBc IgG-positive patients if an allogeneic HSCT is to be performed.

Osteoporosis in Patients With Hemophilia: Single-Center Results From a Middle-Income Country.

Increased number of patients with hemophilia have been identified to have osteoporosis at early ages. Low bone mineral density in the setting of hemophilia has been associated with decreased mobility, sedentary life style, on demand treatment or delayed prophylaxis, low body weight and viral infections. The aim of this study was to investigate the impact of hemophilia on bone health of adult patients living in a middle income country. A total of 61 adult patients with hemophilia who were followed at the Hematology Department of Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa were consecutively included in this study. Bone health of the patients was assessed using the bone mineral density (BMD) and vitamin D levels. Z and t scores are used for evaluation of BMD in patients with hemophilia aged < 50 and ≥ 50 years, respectively. Information on treatment and co-morbidities including viral diseases were obtained from the medical files of the recruited patients. Bone mineral density was found normal in 30, and low in 29 patients. Vitamin D levels were below 20 ng/ml in 46 patients. No significant relationship was found between the severity of hemophilia and bone density. Vitamin D levels were significantly lower in patients who had a history of joint intervention. Neither annual bleeding rate nor the treatment modality (on demand versus prophylaxis) were associated with the bone mineral density and vitamin D levels. Annual factor consumption was higher in patients whose bone mineral densities was low both in femoral and lumbar regions. The results of this study depicting the situation of adult hemophilia population from a middle income country show that bone mineral density and vitamin D levels were decreased in a considerable amount of patients at early ages.

The Outcomes of Chronic Myeloid Leukemia Patients With Molecular Warning Responses During Imatinib Treatment According to the European LeukemiaNet 2013 Recommendations.

BACKGROUND: In the European LeukemiaNet (ELN) 2013 recommendations, chronic myeloid leukemia (CML) patients with warning response (WR) were suggested to be monitored closely continuing with the same tyrosine kinase inhibitor (TKI). Differently, the guidelines of the National Comprehensive Cancer Network considers switching to another TKI as an option. PATIENTS AND METHODS: We retrospectively evaluated 73 CML patients receiving first-line imatinib, who were followed and managed in accordance with ELN recommendations. We compared patients with molecular WR with patients with optimal response (OR) and failure regarding short- and long-term outcomes. RESULTS: The cumulative major molecular response (MMR) rates in patients with OR were significantly higher at any time point than those achieved by the WR group. Patients with WR at 3 months had significantly inferior failure-free survival (FFS) than optimal responders, but overall survival (OS) was similar. For 6 and 12 months, the WR and OR groups had similar FFS and OS. Twenty of 23 patients with WR at 12 months achieved MMR during imatinib treatment. CONCLUSION: It takes longer to get to ELN time points with imatinib than second-generation TKIs (2GTKIs). Treatment might fail in a small proportion of the patients with WR during imatinib treatment, but close and careful monitoring and timely switching to 2GTKIs might translate into favorable outcomes. Avoiding early switch to 2GTKIs would prevent patients from experiencing potential toxicities. There is still a need for prospective comparative studies (ie, continuing imatinib treatment vs. switching to 2GTKIs) in patients with WR, to justify the validity of this response category and to explore the benefit of treatment change in these patients.

Coexistence of Hermansky-Pudlak syndrome and JAK2V617F-positive essential thrombocythemia.

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder consisting of oculocutaneous albinism, platelet storage pool deficiency, and lysosomal accumulation of ceroid lipofuscin. The storage pool deficiency of HPS is associated with the lack of dense bodies in the platelets, resulting in impaired response in the secondary phase of aggregation. Patients with HPS have normal coagulation tests; however, their bleeding time is usually prolonged despite normal or increased platelet counts. Essential thrombocythemia (ET) is an uncommon condition, with an incidence of approximately 1.1 per 100,000/year, and it is the most common cause of primary thrombocytosis. JAK2V617F positivity can be observed in approximately half of the patients with ET. Bleeding events in ET have usually been associated with acquired von Willebrand syndrome paradoxically occurring when the platelet counts are extremely high. We, herein, present a case with bleeding diathesis diagnosed as having both HPS and JAK2V617F-positive ET.

Comparison of different cryopreservation protocols for human umbilical cord tissue as source of mesenchymal stem cells.

The main purpose of this study is to establish an effective cryopreservation protocol for the umbilical cord tissue as a source of mesenchymal stem cells (MSCs). In this context, it was aimed to use a cryoprotectant that could be an alternative to dimethyl sulfoxide (DMSO) which is commonly used despite the toxic side effects. Therefore, two different cryopreservation solutions were prepared using 10% DMSO and 10% 1,2 propanediol (PrOH). The fresh tissue group that was not performed cryopreservation was used as the control group. Following the cryopreservation step, MSCs were isolated from all groups and compared with each other to assess the efficiency of the cryopreservation solutions. The comparison was performed in terms of followings: morphology, immunophenotypes, growth kinetics, differentiation, and ultrastructural features. Based on the results, there were no significant morphological and immunophenotypic differences between the MSCs isolated from cryopreserved tissue groups and the MSCs isolated from the fresh tissue group. According to the growth kinetic analysis, the cells isolated from the PrOH group had a lower proliferation rate than the cells isolated from the fresh tissue. However, there was no significant difference between the cryopreserved groups in this respect. Osteogenic and adipogenic differentiation was observed in all groups. Upon comparison of the cryopreserved groups, PrOH group was discovered to hold a minor superiority in terms of these modes of differentiation. These results suggest that PrOH, which is considered as a cryoprotectant with low toxicity, could be used as a preferred cryoprotectant instead of DMSO concerning the process of cryopreservation of the umbilical cord.

Deep sequencing of BCR-ABL1 kinase domain mutations in chronic myeloid leukemia patients with resistance to tyrosine kinase inhibitors.

Tyrosine kinase inhibitor (TKI) therapy is the current treatment of choice for patients with chronic phase chronic myeloid leukemia (CML) leading to rapid and durable hematological as well as molecular responses. However, emergence of resistance to TKIs has been the major obstacle to treatment success on long term. In this regard kinase domain mutations are the most common mechanism of therapy failure. In this study, we analyzed peripheral blood samples from 17 CML patients who had developed resistance to various TKIs by using next-generation sequencing parallel to Sanger sequencing. BCR-ABL1 kinase domain mutations have been found in 59% of the cohort. Our results demonstrate that next-generation sequencing results in a higher mutational detection rate than reported with conventional sequencing methodology. Furthermore, it showed the clonal diversity more accurately.