Analysis of CSF3R mutations in atypical chronic myeloid leukemia and other myeloid malignancies.

We report a series of patients with CSF3R-mutant (CSF3Rmut) atypical chronic myeloid leukemia (aCML), chronic neutrophilic leukemia (CNL) or other hematologic malignancies. We included 25 patients: 5 aCML and 4 CNL CSF3Rmut patients; 1 aCML, 2 CNL, and 2 myelodysplastic/myeloproliferative neoplasm, not otherwise specified patients without CSF3R mutation; and 11 CSF3Rmut patients with other diseases [8 acute myeloid leukemia (AML), 1 chronic myelomonocytic leukemia (CMML), 1 myelodysplastic syndrome (MDS), and 1 acute lymphoblastic leukemia (ALL)]. Patients with aCML or CNL were tested by Sanger sequencing and pyrosequencing to identify CSF3R T618I. Twenty-two patients underwent gene panel analysis. CSF3R mutations, mostly T618I (8/9), were found at high frequencies in both aCML and CNL patients [5/6 aCML and 4/6 CNL]. Two aCML patients in early adulthood with CSF3R T618I and biallelic or homozygous CEBPA mutations without other mutations presented with increased blasts and exhibited remission for >6 years after transplantation. The other 7 CSF3Rmut aCML or CNL patients were elderly adults who all had ASXL1 mutations and frequently presented with SEBP1 and SRSF2 mutations. Five AML patients had CSF3R exon 14 or 15 point mutations, and 6 other patients (3 AML, 1 CMML, 1 MDS, and 1 ALL) had truncating mutations, demonstrating differences in leukocyte counts and mutation status. In conclusion, CSF3R mutations were found at a higher frequency in aCML patients than in previous studies, which might reflect ethnic differences. Additional studies are needed to confirm these findings and the relationship between CSF3R and CEBPA mutations.

Enhanced Expression of Glycolytic Enzymes and Succinate Dehydrogenase Complex Flavoprotein Subunit A by Mesothelin Promotes Glycolysis and Mitochondrial Respiration in Myeloblasts of Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is an aggressive malignancy characterized by rapid growth and uncontrolled proliferation of undifferentiated myeloid cells. Metabolic reprogramming is commonly observed in the bone marrow of AML patients, as leukemia cells require increased ATP supply to support disease progression. In this study, we examined the potential role of mesothelin as a metabolic modulator in myeloid cells in AML. Mesothelin is a well-known marker of solid tumors that promotes cancer cell proliferation and survival. We initially analyzed alterations in mesothelin expression in the myeloblast subpopulations, defined as SSC-Alow/CD45dim, obtained from the bone marrow of AML patients using flow cytometry. Our results showed overexpression of mesothelin in 34.8% of AML patients. Subsequently, metabolic changes in leukemia cells were evaluated by comparing the oxygen consumption rates (OCR) of bone marrow samples derived from adult AML patients. Notably, a higher OCR was observed in the mesothelin-positive compared to the mesothelin-low and non-expressing groups. Treatment with recombinant human mesothelin protein enhanced OCR and increased the mRNA expression of glycolytic enzymes and mitochondrial complex II in KG1α AML cells. Notably, siRNA targeting mesothelin in KG1α cells led to the reduction of glycolysis-related gene expression but had no effect on the mitochondrial complex gene. The collective results demonstrate that mesothelin induces metabolic changes in leukemia cells, facilitating the acquisition of a rapid supply of ATP for proliferation in AML. Therefore, the targeting of mesothelin presents a potentially promising approach to mitigating the progression of AML through the inhibition of glycolysis and mitochondrial respiration in myeloid cells.

Real-World Treatment Patterns and Clinical Outcomes in Korean Patients With AML Ineligible for First-Line Intensive Chemotherapy: A Subanalysis of the CURRENT Study, a Non-Interventional, Retrospective Chart Review.

BACKGROUND: Although most elderly patients with acute myeloid leukemia (AML) are ineligible for intensive chemotherapy (ICT), treatment options remain limited. CURRENT (UMIN000037786), a real-world, non-interventional, retrospective chart review, evaluated clinical outcomes, clinicopathologic characteristics, and treatment patterns in these patients. We present results from a subanalysis of Korean patients in this study. METHODS: Patients were aged ≥ 18 years with primary or secondary AML ineligible for ICT who initiated first-line systemic therapy or best supportive care (BSC) between 2015 and 2018 across four centers in Korea. Primary endpoint was overall survival (OS) from diagnosis. Secondary endpoints included progression-free survival (PFS), time to treatment failure, and response rates. Data analyses were primarily descriptive, with time-to-event outcomes estimated using the Kaplan-Meier method, and Cox regression used to determine prognostic factors for survival. RESULTS: Among 194 patients enrolled, 84.0% received systemic therapy and 16.0% received BSC. Median age at diagnosis was 74 and 78 years, and Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1 was reported in 73.0% and 48.4% of patients, respectively; poor cytogenetic risk was reported in 30.1% and 16.1% of patients. Median OS was 7.83 vs. 4.50 months, and median PFS was 6.73 vs. 4.50 months in the systemic therapy vs. BSC groups. Prognostic factors affecting OS included secondary AML (hazard ratio, 1.67 [95% confidence interval, 1.13-2.45]), ECOG performance status ≥ 2 (2.41 [1.51-3.83]), poor cytogenetic risk (2.10 [1.36-3.24]), and Charlson comorbidity index ≥ 1 (2.26 [1.43-3.58]). CONCLUSION: Clinical outcomes are poor in Korean patients with AML ineligible for ICT who are prescribed current systemic therapies or BSC. There is a substantial unmet need for novel agents (monotherapy or in combination) to improve clinical outcomes in this patient population.

Abdominal aortic calcification in patients newly diagnosed with essential thrombocythemia.

Background: Although atherosclerosis is likely to be involved in the development of arterial thrombotic events in patients with essential thrombocythemia (ET), abdominal aortic calcification (AAC) has rarely been investigated. We evaluated the prevalence and clinical relevance of AAC at the time of ET diagnosis. Methods: This retrospective study included patients newly diagnosed with ET who underwent abdominal computed tomography (CT) at the time of diagnosis between January 2002 and December 2021 at Chungnam National University Hospital, Daejeon, Korea. CT images were reviewed and an aortic calcification score was assigned. Results: Of the 94 patients (median age, 62 yr; range, 18‒90 yr), AAC was detected in 62 (66.0%). AAC was most commonly mild (33.0%), followed by moderate (22.7%) and severe (5.3%). Old age [odds ratio (OR), 34.37; 95% confidence interval (CI), 12.32‒95.91; P＜0.001] was an independent risk factor for AAC. The patients with AAC had a higher WBC count (11.8±4.7 vs. 9.7±2.9×109/L, P=0.017), higher neutrophil-to-lymphocyte ratio (4.3±2.7 vs. 3.1±1.5, P=0.039), and higher JAK2V617F positivity (81.5% vs. 58.8%, P=0.020) compared to those without AAC. AAC was an independent risk factor for arterial thrombotic vascular events that occurred before or at diagnosis of ET (OR, 4.12; 95% CI, 1.11‒15.85; P=0.034). Conclusion: AAC is common in patients with ET and is associated with arterial thrombotic events.

Autoimmune Limbic Encephalitis in Patients with Hematologic Malignancies after Haploidentical Hematopoietic Stem Cell Transplantation with Post-Transplant Cyclophosphamide.

Autoimmune limbic encephalitis (LE) is a rare, but devastating complication of allogeneic hematopoietic stem cell transplantation (HSCT). There is currently limited evidence describing the risk factors, laboratory features, and underlying mechanisms of this neurologic adverse event. We retrospectively reviewed available clinical, imaging, and laboratory data from adult patients with hematological malignancies who underwent haploidentical HSCT with post-transplant cyclophosphamide (PTCy) at Chungnam National University Hospital from June 2016 to May 2020. Patients who developed LE were compared to those who did not based on clinical assessment, serum inflammatory biomarkers, and reconstitution of various T cell populations. Of 35 patients, 4 developed LE. There were no differences in patient demographics, donor demographics, or treatment conditions between patients that did and did not develop LE. Overall, patients with LE had worse clinical outcomes and overall survival than those without. In addition, they tended to have higher markers of systemic inflammation in the early post-transplant period, including fever, C-reactive protein (CRP), and cytokines. Remarkably, baseline interleukin-6 levels before HSCT were found to be higher in patients who developed LE than those who did not. In addition, analysis of T cell subsets showed impaired expansion of CD25+FOXP3+ regulatory T (Treg) cells in LE compared to non-LE patients despite appropriate reconstitution of the total CD4+ T cell population. Patients that developed LE within the first 30 days of HSCT were likely to have high serum IL-6 among other inflammatory cytokines coupled with suppression of regulatory T cell differentiation. Further work is needed on the mechanisms underlying impaired Treg expansion following HSCT and potential therapies.

Prognostic value of the mutation types and dynamics of FLT3-ITD in acute myeloid leukemia.

OBJECTIVE: The prognostic value of the mutation types and dynamics of FLT3-ITD in acute myeloid leukemia (AML) and other known factors were studied. METHODS: Initial and follow-up samples from 45 AML patients with FLT3-ITD mutations were analyzed by fragment length analysis, Sanger sequencing, and next-generation sequencing. RESULTS: Some patients (13%) had multiple FLT3-ITD mutations, and many of them had acute promyelocytic leukemia (APL). FLT3-ITD mutations were classified according to mutation types, including duplication-only FLT3-ITD (52%) and FLT3-ITD with duplications and insertions (dup + ins) (48%). The dup + ins FLT3-ITD variant was independently associated with poor prognosis among non-APL patients (odds ratio, 2.92) in addition to FLT3-ITD with ≥50% variant allele frequency (VAF). The VAFs of FLT3-ITD were low (median 2.2%) when detected during morphologic complete remission (CR) after conventional chemotherapy; however, in two patients treated with gilteritinib after relapse, the VAFs of FLT3-ITD were much higher (>95% and 8.1%) in the morphologic CR state. CONCLUSIONS: The type of FLT3-ITD mutation is important in prognosis, and the dup + ins type of FLT3-ITD can be an indicator of poor prognosis. In addition, the FLT3-ITD mutation status may unexpectedly not match the morphologic examination results after gilteritinib treatment.

Maintenance therapy with Fluoropyrimidine and cetuximab or bevacizumab after first line FOLFOX-chemotherapy in metastatic colorectal cancer according to RAS or BRAFV600E mutation status.

PURPOSE: Fluoropyrimidine (FP) with oxaliplatin-based chemotherapy is the standard first-line treatment for metastatic colorectal cancer (mCRC); however, oxaliplatin-induced neuropathy critically affects the quality of life of patients. Maintenance strategies with FP plus bevacizumab have been well-established; nonetheless, the real-world outcomes of maintenance therapy with FP and cetuximab are unclear. We investigated the clinical outcomes of patients who underwent maintenance therapy with cetuximab. METHODS: We retrospectively identified and analyzed patients with mCRC who were treated between 2012 and 2021 with first-line oxaliplatin-based induction chemotherapy (IC) plus biologic agents (either cetuximab or bevacizumab), and underwent maintenance therapy (IC regimen without oxaliplatin) after IC. RESULTS: In total, 19 patients who were treated with mFOLFOX6 (FP/leucovorin/oxaliplatin) with cetuximab, and 26 patients who were treated with mFOLFOX6 with bevacizumab were included. In the cetuximab group, all patients were KRAS-, NRAS-, and BRAF-wild type, whereas most patients in the bevacizumab group harbored KRAS or BRAFV600E or NRAS mutants. During the maintenance treatment, seven patients (four [21%] in the cetuximab group and three [11%] in the bevacizumab group) achieved partial response after achieving nadir during induction chemotherapy. The disease control rates of maintenance therapy were 79% and 74% in the cetuximab and bevacizumab groups, respectively. The median progression-free survival of maintenance therapy and overall survival was 5.98 months and 32.4 months in the cetuximab group, and 4.83 months and 25.6 months in the bevacizumab group, respectively. CONCLUSIONS: Maintenance therapy with FP plus biologic agents (either bevacizumab or cetuximab) is a feasible strategy for appropriate mCRC patients according to their RAS/BRAF status. Further large-scale randomized studies are needed to validate the efficacy of anti-epidermal growth factor receptor-based maintenance therapy.

Efficacy of cisplatin combined with vinorelbine as second- or higher-line palliative chemotherapy in patients with advanced ovarian cancer.

The aim of this study was to assess the therapeutic efficacy of a cisplatin and vinorelbine combination as second- or higher-line palliative chemotherapy in patients with advanced ovarian cancer. We retrospectively reviewed the medical records of patients with advanced ovarian cancer who were treated with cisplatin (60 mg/m2 on day 1) and vinorelbine (25 mg/m2 on days 1 and 8) every 3 weeks between January 2004 and March 2021. Treatment responses, progression-free survival (PFS), and overall survival (OS) were assessed; laboratory data were reviewed to determine toxicity. Thirty-two patients with advanced ovarian cancer were treated with a combination of vinorelbine and cisplatin. The objective response rate (ORR) was 18.8% and the disease control rate was 75.1%. The median PFS was 4.13 months (95% confidence interval [CI], 2.4-5.8 months). The median OS was 56.9 months (95% CI, 50.5-63.7 months). The ORR (42.9% vs 9.1%; P = .035) was higher in the platinum-sensitive group than in the platinum-resistant group. The median PFS tended to be longer in the platinum-sensitive group (5.3 vs 3.8 months; P = .339) and the median OS was significantly longer in the platinum-sensitive group than in the platinum-resistant group (69.6 vs 24 months; P < .001). All patients developed hematological toxicities, with 56% experiencing grade 3 to 4 neutropenia. Two (6.2%) patients developed febrile neutropenia, but no treatment-related death occurred. This combination therapy may be effective in patients with heavily treated advanced ovarian cancer, particularly in platinum-sensitive patients.

Acquired von willebrand syndrome in patients with philadelphia-negative myeloproliferative neoplasm.

Background: Acquired von Willebrand syndrome (AVWS) has not been investigated in Korean patients with Philadelphia chromosome-negative myeloproliferative neoplasm. Methods: This study analyzed the prevalence at diagnosis and clinical features of AVWS in patients with essential thrombocythemia (ET), polycythemia vera (PV), prefibrotic/early primary myelofibrosis (pre-PMF), or overt PMF (PMF) diagnosed between January 2019 and December 2021 at Chungam National University Hospital, Daejeon, Korea. AVWS was defined as below the lower reference limit (56%) of ristocetin cofactor activity (VWF:RCo). Results: Sixty-four consecutive patients (36 with ET, 17 with PV, 6 with pre-PMF, and 5 with PMF; 30 men and 34 women) with a median age of 67 years (range, 18‒87 yr) were followed for a median of 25.1 months (range, 2.6‒46.4 mo). AVWS was detected in 20 (31.3%) patients at diagnosis and was most frequent in ET patients (41.4%), followed by patients with pre-PMF (33.3%) and PV (17.6%) patients. VWF:RCo was negatively correlated with the platelet count (r=0.937; P=0.002). Only one episode of minor bleeding occurred in a patient with ET and AVWS. Younger age (<50 yr) [odds ratio (OR), 7.08; 95% confidence interval (CI), 1.27‒39.48; P=0.026] and thrombocytosis (>600×109/L) (OR, 13.70; 95% CI, 1.35‒138.17; P=0.026) were independent risk factors for developing AVWS. Conclusion: AVWS based on VWF:RCo was common in patients with ET and pre-PMF, but less common in patients with PV in the Korean population. Clinically significant bleeding is rare in these patients.

Cardiopulmonary Exercise Test With Comorbidity Index Before Allogeneic Hematopoietic Stem Cell Transplantation.

PURPOSE: To evaluate the role of the cardiopulmonary exercise test (CPET) with comorbidity index as a predictor of overall survival (OS) and non-relapse mortality (NRM) in patients with hematological malignancies who undergo allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: We retrospectively analyzed consecutive adult patients with hematological malignancies who underwent HLA-matched donor-HSCT at Chungnam National University Hospital (Daejeon, South Korea) between January 2014 and December 2020. Maximal oxygen consumption (VO2max) was classified using the recommendations of the Mayo Clinic database. RESULTS: Of 72 patients, 38 (52.8%) had VO2max values lower than the 25th percentile (VO2max ≤ 25th) of an age- and sex-matched normal population. Patients with VO2max ≤ 25th had no significant differences both OS and NRM (30 month OS 29.8% vs 41%, P = .328; and 30 month NRM 16% vs 3.3%, P = .222), compared with other patients. VO2max ≤ 25th was assigned a weight of 1 when added to the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) to form a composite comorbidity/CPET index (HCT-CI/CPET). Patients with HCT-CI/CPET scores of 0 to 1 demonstrated significantly better OS and NRM than did patients with HCT-CI/CPET scores ≥2 [median OS not reached vs 6 months, P < .001 and 30 month NRM 7.4% vs 33.3%, P = .006]. An HCT-CI/CPET score ≥2 was the only adverse risk factor for NRM on multivariate analysis [hazard ratio (HR) of NRM 10.36 (95% CI 1.486-2.25, P = .018)]. CONCLUSION: The composite HCT-CI/CPET score can predict the survival and mortality of patients with hematological malignancies who undergo allogeneic HSCT.

Targeting ERRα promotes cytotoxic effects against acute myeloid leukemia through suppressing mitochondrial oxidative phosphorylation.

Acute myeloid leukemia (AML) is an aggressive blood cancer with poor clinical outcomes. Emerging data suggest that mitochondrial oxidative phosphorylation (mtOXPHOS) plays a significant role in AML tumorigenesis, progression, and resistance to chemotherapies. However, how the mtOXPHOS is regulated in AML cells is not well understood. In this study, we investigated the oncogenic functions of ERRα in AML by combining in silico, in vitro, and in vivo analyses and showed ERRα is a key regulator of mtOXPHOS in AML cells. The increased ERRα level was associated with worse clinical outcomes of AML patients. Single cell RNA-Seq analysis of human primary AML cells indicated that ERRα-expressing cancer cells had significantly higher mtOXPHOS enrichment scores. Blockade of ERRα by pharmacologic inhibitor (XCT-790) or gene silencing suppressed mtOXPHOS and increased anti-leukemic effects in vitro and in xenograft mouse models.

Gene Set Enrichment Analysis Reveals That Fucoidan Induces Type I IFN Pathways in BMDC.

Fucoidan, a sulfated polysaccharide extracted from brown seaweed, has been proposed to effectively treat and prevent various viral infections. However, the mechanisms behind its antiviral activity are not completely understood. We investigate here the global transcriptional changes in bone marrow-derived dendritic cells (BMDCs) using RNA-Seq technology. Through both analysis of differentially expressed genes (DEG) and gene set enrichment analysis (GSEA), we found that fucoidan-treated BMDCs were enriched in virus-specific response pathways, including that of SARS-CoV-2, as well as pathways associated with nucleic acid-sensing receptors (RLR, TLR, NLR, STING), and type I interferon (IFN) production. We show that these transcriptome changes are driven by well-known regulators of the inflammatory response against viruses, including IRF, NF-κB, and STAT family transcription factors. Furthermore, 435 of the 950 upregulated DEGs are classified as type I IFN-stimulated genes (ISGs). Flow cytometric analysis additionally showed that fucoidan increased MHCII, CD80, and CD40 surface markers in BMDCs, indicative of greater antigen presentation and co-stimulation functionality. Our current study suggests that fucoidan transcriptionally activates PRR signaling, type I IFN production and signaling, ISGs production, and DC maturation, highlighting a potential mechanism of fucoidan-induced antiviral activity.

The dual role of autophagy in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a severe hematologic malignancy prevalent in older patients, and the identification of potential therapeutic targets for AML is problematic. Autophagy is a lysosome-dependent catabolic pathway involved in the tumorigenesis and/or treatment of various cancers. Mounting evidence has suggested that autophagy plays a critical role in the initiation and progression of AML and anticancer responses. In this review, we describe recent updates on the multifaceted functions of autophagy linking to genetic alterations of AML. We also summarize the latest evidence for autophagy-related genes as potential prognostic predictors and drivers of AML tumorigenesis. We then discuss the crosstalk between autophagy and tumor cell metabolism into the impact on both AML progression and anti-leukemic treatment. Moreover, a series of autophagy regulators, i.e., the inhibitors and activators, are described as potential therapeutics for AML. Finally, we describe the translation of autophagy-modulating therapeutics into clinical practice. Autophagy in AML is a double-edged sword, necessitating a deeper understanding of how autophagy influences dual functions in AML tumorigenesis and anti-leukemic responses.

Splenic Infarction in Patients with Philadelphia-negative Myeloproliferative Neoplasms.

Objective We retrospectively analyzed the prevalence and clinical features of splenic infarctions in patients with Philadelphia chromosome-negative myeloproliferative neoplasms (Ph- MPNs). Patients Patients diagnosed with essential thrombocythemia (ET), polycythemia vera (PV), prefibrotic/early primary myelofibrosis (pre-PMF), or PMF from January 1996 to October 2020 in Chungnam National University Hospital, Daejeon, Korea, were reviewed. Results A total of 347 patients (143 ET, 129 PV, 44 pre-PMF, and 31 PMF patients; 201 men and 146 women) with a median age of 64 (range 15-91) years old were followed up for a median of 4.7 (range 0.1-26.5) years. Fifteen (4.3%) patients exhibited splenic infarctions at the diagnosis. These were most common in PMF patients (12.9%), followed by pre-PMF (9.1%) and PV (5.4%) patients. Multifocal infarcts (60.0%) were most common, followed by solitary (33.3%) and extensive infarcts (6.7%). The cumulative incidence of thrombosis in patients with splenic infarctions tended to be higher than in those lacking infarctions (10-year incidence 46.7% vs. 21.0% in PV; p=0.215; 33.3% vs. 17.9% in pre-PMF; p=0.473) patients, but statistical significance was lacking. Palpable splenomegaly (hazard ratio 14.89; 95% confidence interval 4.00-55.35; p<0.001) was the only independent risk factor for splenic infarction. During follow-up, 5 (1.4%) patients developed splenic infarctions. Conservative treatment adequately controlled the symptoms; no serious complications were noted in any patient. Conclusion Splenic infarctions occurred most frequently in patients with PMF; it was rare in patients with ET. The clinical courses were generally mild.

Volumetric Splenomegaly in Patients With Polycythemia Vera.

BACKGROUND: Non-palpable splenomegaly in patients with polycythemia vera (PV) has seldom been addressed. In this retrospective study, we evaluated non-palpable, volumetric splenomegaly defined based on age- and body surface area (BSA)-matched criteria in patients with PV diagnosed according to the 2016 World Health Organization diagnostic criteria. METHODS: Patients with PV who underwent abdominal computed tomography (CT) and who had palpable splenomegaly at diagnosis from January 1991 to December 2020 at Chungnam National University Hospital were enrolled. The spleen volume of each patient was determined by volumetric analysis of abdominal CT and adjusted for the patient's age and BSA. Then the degree of splenomegaly was classified as no splenomegaly, borderline volumetric splenomegaly, overt volumetric splenomegaly, or palpable splenomegaly. RESULTS: Of the 87 PV patients enrolled, 15 (17.2%) had no splenomegaly, whereas 17 (19.5%), 45 (51.7%), and 10 (11.5%) had borderline volumetric, overt volumetric, and palpable splenomegaly, respectively. The degree of splenomegaly did not affect the cumulative incidence of thrombotic vascular events (10-year incidence: 7.7%, 0%, 22.3%, and 50.7%, respectively, P = 0.414). By contrast, splenomegaly tended to adversely affect myelofibrotic transformation (10-year cumulative incidence: 0%, 0%, 7.1%, and 30.3%, respectively, P = 0.062). Moreover, the cumulative incidence of myelofibrotic transformation was significantly higher in patients with overt volumetric or palpable splenomegaly than those with no or borderline volumetric splenomegaly (10-year incidence: 0% vs. 10.3%, respectively; 15-year incidence: 0% vs. 26.3%, respectively, P = 0.020). Overall survival (OS) differed among patients with different degrees of splenomegaly (15-year OS: 100%, 78.6%, 71.7%, and 51.9%, respectively, P = 0.021). CONCLUSION: The degree of splenomegaly, including volumetric splenomegaly, based on age- and BSA-matched reference spleen volumes at diagnosis reflects disease progression in PV patients. Therefore, volumetric splenomegaly should be evaluated at the time of diagnosis and taken into consideration when predicting the prognosis of patients with PV.

Myelofibrotic and leukemic transformation in 2016 WHO-defined Philadelphia-negative myeloproliferative neoplasm.

Background: Information on myelofibrotic and leukemic transformations in Korean Philadelphia chromosome- negative myeloproliferative neoplasms (Ph‒ MPNs) is limited. Methods: This study retrospectively analyzed transformations in patients diagnosed with essential thrombocythemia (ET), polycythemia vera (PV) prefibrotic/early primary myelofibrosis (pre-PMF), or overt primary myelofibrosis (PMF) based on the 2016 World Health Organization criteria between January 1996 and December 2020 at Chungam National University Hospital, Daejeon, Korea. Results: A total of 351 patients (144 with ET, 131 with PV, 45 with pre-PMF, and 31 with PMF; 204 men and 147 women) with a median age of 64 years (range, 15‒91 years) were followed for a median of 4.6 years (range, 0.2‒24.8 years). The 10-year incidence of overt myelofibrosis was higher in pre-PMF than in ET (31.3% and 13.7%, respectively; P =0.031) and PV (12.2%; P =0.003). The 10-year incidence of leukemic transformation was significantly higher in PMF than in ET (40.0% and 7.9%, respectively; P =0.046), pre-PMF (4.7%; P =0.048), and PV (3.2%; P =0.031). The 5-year incidence of leukemic transformation was higher in patients with secondary myelofibrosis (SMF) than in those with PMF (19.0% and 11.4%, respectively; P =0.040). The 5-year overall survival of patients with SMF was significantly worse than that of patients with pre-PMF (74% and 93%, respectively; P=0.027) but did not differ from that of patients with PMF (57%; P=0.744). Conclusion: The rates and clinical courses of myelofibrotic and leukemic transformations in Korean patients with Ph‒ MPN did not differ from those in Western populations.

Pulmonary hypertension in patients with chronic myeloid leukemia.

ABSTRACT: Dasatinib, a tyrosine kinase inhibitor (TKI), induces pulmonary hypertension (PH) in patients with chronic myeloid leukemia (CML). However, information on other TKIs is limited.We retrospectively analyzed PH prevalence by reviewing transthoracic echocardiography (TTE) findings in a population of Korean CML patients treated with TKI at a single hospital between 2003 and 2020. PH was defined as a high PH probability according to the European Society of Cardiology/European Respiratory Society (ESC/ERS) guidelines.Of the 189 patients treated with TKI(s) during the study period, 112 (59.3%) underwent TTE. Among the 112 patients treated with a TKI for a median of 40.4 months (range: 1.1-167.2 months), PH was found in 12 (10.7%), most frequently in those treated with dasatinib (ie, in 3 [7.5%] of 40 of those treated with imatinib, 1 [3.1%] of 32 of those treated with nilotinib, and 8 [21.6%] of 37 of those treated with dasatinib). PH resolved in 4 (50.0%) of the 8 dasatinib-treated patients after discontinuation of the agent. One nilotinib-treated and all three imatinib-treated patients recovered from PH. In multivariate analyses, age >60 years, dasatinib treatment, and positive cardiopulmonary symptoms/signs at the time of transthoracic echocardiography were statistically significant risk factors for developing PH.These results show that PH is induced not only by dasatinib, but also by imatinib and nilotinib. Careful screening for PH during any TKI treatment may thus be warranted in patients with CML.

Thrombotic and hemorrhagic events in 2016 World Health Organization-defined Philadelphia-negative myeloproliferative neoplasm.

BACKGROUND/AIMS: Recent changes in the diagnostic criteria for myeloproliferative neoplasms (MPNs) and increasing patient numbers necessitate updating of the data on vascular events in patients with such disorders. METHODS: In this single-center study, thrombotic and hemorrhagic events were retrospectively analyzed in patients diagnosed with essential thrombocythemia (ET), polycythemia vera (PV) prefibrotic/early primary myelofibrosis (pre-PMF), or PMF, based on the 2016 World Health Organization diagnostic criteria. RESULTS: Of a total of 335 consecutive patients (139 ET, 42 pre-PMF, 124 PV, and 30 PMF patients; 192 males and 143 females) of median age 64 years (range, 15 to 91), 112 (33.4%) experienced a total of 126 thrombotic events before diagnosis, at the time of diagnosis, or during follow-up over a median of 4.6 years (range, 0.1 to 26.5). Cerebrovascular thrombosis (18.8%) was the most common initial event, followed by coronary heart disease (10.1%) and splanchnic (1.5%) and peripheral thrombosis (1.5%). Arterial thrombosis was more common than venous thrombosis (31.3% vs. 2.1%, respectively; p = 0.001). Thrombosis was most frequent in PV patients (39.5%), followed by patients with pre-PMF (38.1%), ET (30.9%), and PMF (13.3%). Of the 112 patients who experienced thromboses, 53 (47%) and 39 (33.9%) had thrombotic events before and at the time of MPN diagnosis, respectively. Twenty-seven patients (8.1%) experienced 29 hemorrhagic events, of which gastrointestinal bleeding (n = 20) was the most common. CONCLUSION: Most thrombotic events occurred before or at the time of diagnosis, and the prevalence of arterial thrombosis was markedly higher than that of venous thrombosis in patients with MPN.

Volumetric splenomegaly in patients with essential thrombocythemia and prefibrotic/early primary myelofibrosis.

Non-palpable, volumetric splenomegaly at diagnosis was evaluated using computed tomography in patients with essential thrombocythemia (ET) and prefibrotic/early primary myelofibrosis (pre-PMF) based on 2016 World Health Organization guidelines. Each patient's spleen volume was adjusted for their age and body surface area. The degree of splenomegaly was classified as no, borderline volumetric, overt volumetric, or palpable splenomegaly. Seventy-six patients with ET (median age, 62.5 years) and 19 patients with pre-PMF (median age, 65 years) were followed up for a median of 2.4 years (range 0.1-17.6 years) and 4.2 years (range 0.2-19.6 years), respectively. Spleen volume was significantly greater in pre-PMF patients than in ET patients (377.9 ± 92.2 cm3 vs. 224.9 ± 115.2 cm3, P < 0.001). No, borderline volumetric, overt volumetric, and palpable splenomegaly were found in 42 (55.3%), 24 (31.6%), 10 (13.2%), and 0 (0%) patients with ET, respectively, and in 0 (0%), 8 (42.1%), 19 (52.6%), and 1 (5.2%) patient with pre-PMF, respectively (P < 0.001). Volumetric splenomegaly did not affect thrombosis-free survival in patients with ET or those with pre-PMF. This study indicates that all patients with pre-PMF present with splenomegaly, whereas half of the patients with ET have a normal-sized spleen at diagnosis.