Real-world data on diagnostics, treatment and outcomes of patients with hairy cell leukemia: The HCL-CLLEAR study.

Hairy cell leukemia (HCL) and HCL-like disorders have to be distinguished because of their different biology and treatment response. Thus, we conducted a retrospective study on patients with HCL and hairy cell leukemia variant (HCLv) to assess diagnostic algorithms and treatment outcomes in a real-world setting. We analyzed 225 HCL and 26 HCLv patients with median follow-up of 67.9 months (HCL) and 20.1 months (HCLv). Median age at diagnosis was 56.2 (HCL) and 69.5 years (HCLv), male predominance was observed in both groups (76.0% vs. 73.1%). Diagnostics was mostly based on morphological evidence of hairy cells in the peripheral blood and bone marrow. At diagnosis, BRAF V600E mutation was detected in 94.7% of examined HCL patients and in no HCLv patient. Front-line treatment was indicated in 205 (91.1%) HCL and 18 (69.2%) HCLv patients. The majority of HCL patients were administered a cladribine-based regimen (91.2%). Overall response rate (ORR) was higher in cladribine-treated patients compared to those given other treatments (97.7% vs. 81.3%), the same applied with achieving Complete remission (CR) (91.2% vs. 62.5%). HCLv treatment was heterogeneous, but cladribine remained the most frequent option (44.4%) with ORR 81.3% and CR rates 43.8%. Second-line treatment was indicated in 52 HCL and 8 HCLv patients, 25.4% and 44.4% of those treated in first-line. In the whole HCL group, median time to next treatment (TTNT) was not reached and 10-year TTNT was estimated at 74.1%. HCLv patients who underwent first-line treatment had a median TTNT of 56 months. The median overall survival (OS) in HCL patients was not reached compared to HCLv with a median OS of 9.5 years. These data confirm an excellent prognosis for HCL patients treated with cladribine-based therapy. On the contrary, HCLv with its aggressive behavior represents a group of patients in whom novel treatment approaches are needed.

Unveiling the dynamics and molecular landscape of a rare chronic lymphocytic leukemia subpopulation driving refractoriness: insights from single-cell RNA sequencing.

Early identification of resistant cancer cells is currently a major challenge, as their expansion leads to refractoriness. To capture the dynamics of these cells, we made a comprehensive analysis of disease progression and treatment response in a chronic lymphocytic leukemia (CLL) patient using a combination of single-cell and bulk genomic methods. At diagnosis, the patient presented with unfavorable genetic markers, including notch receptor 1 (NOTCH1) mutation and loss(11q). The initial and subsequent treatment lines did not lead to a durable response and the patient developed refractory disease. Refractory CLL cells featured substantial dysregulation in B-cell phenotypic markers such as human leukocyte antigen (HLA) genes, immunoglobulin (IG) genes, CD19 molecule (CD19), membrane spanning 4-domains A1 (MS4A1; previously known as CD20), CD79a molecule (CD79A) and paired box 5 (PAX5), indicating B-cell de-differentiation and disease transformation. We described the clonal evolution and characterized in detail two cell populations that emerged during the refractory disease phase, differing in the presence of high genomic complexity. In addition, we successfully tracked the cells with high genomic complexity back to the time before treatment, where they formed a rare subpopulation. We have confirmed that single-cell RNA sequencing enables the characterization of refractory cells and the monitoring of their development over time.

Serum chemistry profiling and prognostication in systemic mastocytosis: a registry-based study of the ECNM and GREM.

Certain laboratory abnormalities correlate with subvariants of systemic mastocytosis (SM) and are often prognostically relevant. To assess the diagnostic and prognostic value of individual serum chemistry parameters in SM, 2607 patients enrolled within the European Competence Network on Mastocytosis (ECNM) and 575 patients enrolled within the German Registry on Eosinophils and Mast Cells (GREM) were analyzed. For screening and diagnosis of SM, tryptase was identified as the most specific serum parameter. For differentiation between indolent and advanced SM (AdvSM), the following serum parameters were most relevant: tryptase, alkaline phosphatase (AP), ß2-microglobulin, lactate dehydrogenase (LDH), albumin, vitamin B12, and C-reactive protein (P<0.001). With regard to subvariants of AdvSM, an elevated LDH ≥260U/L was associated with multi-lineage expansion (leukocytosis, r=0.37, P<0.001; monocytosis, r=0.26, P<0.001) and the presence of an associated myeloid neoplasm (P<0.001), whereas tryptase levels were highest in mast cell leukemia (MCL vs. non-MCL, 308 µg/L vs. 146 µg/L, P=0.003). Based on multivariable analysis, the hazard-risk weighted assignment of 1 point to lactate dehydrogenase (HR 2.1 [95% CI 1.1-4.0], P=0.018) and 1.5 points each to ß2-microglobulin (HR 2.7 [95% CI 1.4-5.4], P=0.004) and albumin (HR 3.3 [95% CI 1.7-6.5], P=0.001) delineated a highly predictive three-tier risk classification system (0 points, 8.1 years vs. 1 point, 2.5 years, ≥1.5 points, 1.7 years; P<0.001). Moreover, serum chemistry parameters enabled further stratification of IPSM-AdvSM1/2 risk-score classified patients (P=0.027). In conclusion, serum chemistry profiling is a crucial tool in the clinical practice supporting diagnosis and prognostication of SM and its subvariants.

Prevalence of hypersensitivity reactions in various forms of mastocytosis: A pilot study of 2485 adult patients with mastocytosis collected in the ECNM registry.

BACKGROUND: Hypersensitivity reactions (HR) are common in mastocytosis. However, little is known about triggers and risk factors. The registry of the European Competence Network on Mastocytosis (ECNM) enables reliable studies in a larger cohort of mastocytosis patients. We assessed prevalence, triggers and risk factors of HR in adults with mastocytosis in the ECNM registry. METHODS: Data were collected in 27 ECNM centers. We analyzed potential triggers (Hymenoptera venoms, food, drug, inhalant and others) and risk factors at diagnosis and during follow-up. The study group consisted of 2485 adults with mastocytosis, 1379 women (55.5%) and 1106 men (44.5%). Median age was 48.2 years (range 18-91 years). RESULTS: Nine hundred and forty eight patients (38.1%) reported one or more HR`. Most common triggers were Hymenoptera venoms in cutaneous mastocytosis (CM) and indolent systemic mastocytosis (ISM), whereas in advanced SM (advSM), most common elicitors were drugs, including nonsteroidal anti-inflammatory agents and penicillin. In multivariate analyses, tryptase level < 90 ng/mL, <15% infiltration by mast cells in bone marrow biopsy-sections, and diagnosis of ISM were identified as independent risk factors for HR. For drug-induced HR, prominent risk factors were advSM and high tryptase levels. New reactions were observed in 4.8% of all patients during 4 years follow-up. CONCLUSIONS: HR are mainly triggered by Hymenoptera venoms in patients with CM and ISM and by drugs in patients with advSM. Tryptase levels <90 ng/mL, mast cell bone marrow infiltration <15%, and WHO category ISM are predictors of HR. New HR occur in 4.8% of all patients within 4 years.

Management of ALL in adults: 2024 ELN recommendations from a European expert panel.

ABSTRACT: Experts from the European Leukemia Net (ELN) working group for adult acute lymphoblastic leukemia have identified an unmet need for guidance regarding management of adult acute lymphoblastic leukemia (ALL) from diagnosis to aftercare. The group has previously summarized their recommendations regarding diagnostic approaches, prognostic factors, and assessment of ALL. The current recommendation summarizes clinical management. It covers treatment approaches, including the use of new immunotherapies, application of minimal residual disease for treatment decisions, management of specific subgroups, and challenging treatment situations as well as late effects and supportive care. The recommendation provides guidance for physicians caring for adult patients with ALL which has to be complemented by regional expertise preferably provided by national academic study groups.

Diagnosis, prognostic factors, and assessment of ALL in adults: 2024 ELN recommendations from a European expert panel.

ABSTRACT: Working groups of the European LeukemiaNet have published several important consensus guidelines. Acute lymphoblastic leukemia (ALL) has many different clinical and biological subgroups and the knowledge on disease biology and therapeutic options is increasing exponentially. The European Working Group for Adult ALL has therefore summarized the current state of the art and provided comprehensive consensus recommendations for diagnostic approaches, biologic and clinical characterization, prognostic factors, and risk stratification as well as definitions of endpoints and outcomes. Aspects of treatment, management of subgroups and specific situations, aftercare, and supportive care are covered in a separate publication. The present recommendation intends to provide guidance for the initial management of adult patients with ALL and to define principles as a basis for future collaborative research.

Integrative NGS testing reveals clonal dynamics of adverse genomic defects contributing to a natural progression in treatment-naïve CLL patients.

Large-scale next-generation sequencing (NGS) studies revealed extensive genetic heterogeneity, driving a highly variable clinical course of chronic lymphocytic leukaemia (CLL). The evolution of subclonal populations contributes to diverse therapy responses and disease refractoriness. Besides, the dynamics and impact of subpopulations before therapy initiation are not well understood. We examined changes in genomic defects in serial samples of 100 untreated CLL patients, spanning from indolent to aggressive disease. A comprehensive NGS panel LYNX, which provides targeted mutational analysis and genome-wide chromosomal defect assessment, was employed. We observed dynamic changes in the composition and/or proportion of genomic aberrations in most patients (62%). Clonal evolution of gene variants prevailed over the chromosomal alterations. Unsupervised clustering based on aberration dynamics revealed four groups of patients with different clinical behaviour. An adverse cluster was associated with fast progression and early therapy need, characterized by the expansion of TP53 defects, ATM mutations, and 18p- alongside dynamic SF3B1 mutations. Our results show that clonal evolution is active even without therapy pressure and that repeated genetic testing can be clinically relevant during long-term patient monitoring. Moreover, integrative NGS testing contributes to the consolidated evaluation of results and accurate assessment of individual patient prognosis.

Extensive, 3.8 Mb-Sized Deletion of 22q12 in a Patient with Bilateral Schwannoma, Intellectual Disability, Sensorineural Hearing Loss, and Epilepsy.

Introduction: In contrast with the well-known and described deletion of the 22q11 chromosome region responsible for DiGeorge syndrome, 22q12 deletions are much rarer. Only a few dozen cases have been reported so far. This region contains genes responsible for cell cycle control, chromatin modification, transmembrane signaling, cell adhesion, and neural development, as well as several cancer predisposition genes. Case Presentation: We present a patient with cleft palate, sensorineural hearing loss, vestibular dysfunction, epilepsy, mild to moderate intellectual disability, divergent strabism, pes equinovarus, platyspondylia, and bilateral schwannoma. Using Microarray-based Comparative Genomic Hybridization (aCGH), we identified the de novo 3.8 Mb interstitial deletion at 22q12.1→22q12.3. We confirmed deletion of the critical NF2 region by MLPA analysis. Discussion: Large 22q12 deletion in the proband encases the critical NF2 region, responsible for development of bilateral schwannoma. We compared the phenotype of the patient with previously reported cases. Interestingly, our patient developed cleft palate even without deletion of the MN1 gene, deemed responsible in previous studies. We also strongly suspect the DEPDC5 gene deletion to be responsible for seizures, consistent with previously reported cases.

The evolving landscape of COVID-19 and post-COVID condition in patients with chronic lymphocytic leukemia: A study by ERIC, the European research initiative on CLL.

In this retrospective international multicenter study, we describe the clinical characteristics and outcomes of patients with chronic lymphocytic leukemia (CLL) and related disorders (small lymphocytic lymphoma and high-count monoclonal B lymphocytosis) infected by SARS-CoV-2, including the development of post-COVID condition. Data from 1540 patients with CLL infected by SARS-CoV-2 from January 2020 to May 2022 were included in the analysis and assigned to four phases based on cases disposition and SARS-CoV-2 variants emergence. Post-COVID condition was defined according to the WHO criteria. Patients infected during the most recent phases of the pandemic, though carrying a higher comorbidity burden, were less often hospitalized, rarely needed intensive care unit admission, or died compared to patients infected during the initial phases. The 4-month overall survival (OS) improved through the phases, from 68% to 83%, p = .0015. Age, comorbidity, CLL-directed treatment, but not vaccination status, emerged as risk factors for mortality. Among survivors, 6.65% patients had a reinfection, usually milder than the initial one, and 16.5% developed post-COVID condition. The latter was characterized by fatigue, dyspnea, lasting cough, and impaired concentration. Infection severity was the only risk factor for developing post-COVID. The median time to resolution of the post-COVID condition was 4.7 months. OS in patients with CLL improved during the different phases of the pandemic, likely due to the improvement of prophylactic and therapeutic measures against SARS-CoV-2 as well as the emergence of milder variants. However, mortality remained relevant and a significant number of patients developed post-COVID conditions, warranting further investigations.

Germline variant of CTC1 gene in a patient with pulmonary fibrosis and myelodysplastic syndrome.

Introduction: Telomeropathies are associated with a wide range of diseases and less common combinations of various pulmonary and extrapulmonary disorders. Case presentation: In proband with high-risk myelodysplastic syndrome and interstitial pulmonary fibrosis, whole exome sequencing revealed a germline heterozygous variant of CTC1 gene (c.1360delG). This "frameshift" variant results in a premature stop codon and is classified as likely pathogenic/pathogenic. So far, this gene variant has been described in a heterozygous state in adult patients with hematological diseases such as idiopathic aplastic anemia or paroxysmal nocturnal hemoglobinuria, but also in interstitial pulmonary fibrosis. Described CTC1 gene variant affects telomere length and leads to telomeropathies. Conclusions: In our case report, we describe a rare case of coincidence of pulmonary fibrosis and hematological malignancy caused by a germline gene mutation in CTC1. Lung diseases and hematologic malignancies associated with short telomeres do not respond well to standard treatment.

European Competence Network on Mastocytosis (ECNM): 20-Year Jubilee, Updates, and Future Perspectives.

In 2002, the European Competence Network on Mastocytosis (ECNM) was launched as a multidisciplinary collaborative initiative to increase the awareness and to improve diagnosis and management of patients with mast cell (MC) disorders. The ECNM consists of a net of specialized centers, expert physicians, and scientists who dedicate their work to MC diseases. One essential aim of the ECNM is to timely distribute all available information about the disease to patients, doctors, and scientists. In the past 20 years, the ECNM has expanded substantially and contributed successfully to the development of new diagnostic concepts, and to the classification, prognostication, and treatments of patients with mastocytosis and MC activation disorders. The ECNM also organized annual meetings and several working conferences, thereby supporting the development of the World Health Organization classification between 2002 and 2022. In addition, the ECNM established a robust and rapidly expanding patient registry and supported the development of new prognostic scoring systems and new treatment approaches. In all projects, ECNM representatives collaborated closely with their U.S. colleagues, various patient organizations, and other scientific networks. Finally, ECNM members have started several collaborations with industrial partners, leading to the preclinical development and clinical testing of KIT-targeting drugs in systemic mastocytosis, and some of these drugs received licensing approval in recent years. All these networking activities and collaborations have strengthened the ECNM and supported our efforts to increase awareness of MC disorders and to improve diagnosis, prognostication, and therapy in patients.

Idelalisib plus rituximab versus ibrutinib in the treatment of relapsed/refractory chronic lymphocytic leukaemia: A real-world analysis from the Chronic Lymphocytic Leukemia Patients Registry (CLLEAR).

Idelalisib (idela), a phosphatidylinositol 3-kinase inhibitor, and ibrutinib, a Bruton tyrosine kinase inhibitor, were the first oral targeted agents approved for relapsed/refractory (R/R) chronic lymphocytic leukaemia (CLL). However, no randomised trials of idelalisib plus rituximab (R-idela) versus ibrutinib have been conducted. Therefore, we performed a real-world retrospective analysis of patients with R/R CLL treated with R-idela (n = 171) or ibrutinib (n = 244). The median age was 70 versus 69 years, with a median of two previous lines. There was a trend towards higher tumour protein p53 (TP53) aberrations and complex karyotype in the R-idela group (53% vs. 44%, p = 0.093; 57% vs. 46%, p = 0.083). The median progression-free survival (PFS) was significantly longer with ibrutinib (40.5 vs. 22.0 months; p < 0.001); similarly to overall survival (OS; median 54.4 vs. 37.7 months, p = 0.04). In multivariate analysis, only PFS but not OS remained significantly different between the two agents. The most common reasons for treatment discontinuation included toxicity (R-idela, 39.8%; ibrutinib, 22.5%) and CLL progression (27.5% vs. 11.1%). In conclusion, our data show significantly better efficacy and tolerability of ibrutinib over R-idela in patients with R/R CLL treated in routine practice. The R-idela regimen may still be considered a reasonable option in highly selected patients without a suitable treatment alternative.

COVID-19 in patients with chronic lymphocytic leukemia: a multicenter analysis by the Czech CLL study group.

Patients with chronic lymphocytic leukemia (CLL) have a high risk of poor outcomes related to coronavirus disease 2019 (COVID-19). This multicenter cohort study evaluated the impact of COVID-19 infection on the population of CLL patients in the Czech Republic. Between March 2020 and May 2021, 341 patients (237 males) with CLL and COVID-19 disease were identified. The median age was 69 years (range 38-91). Out of the 214 (63%) patients with the history of therapy for CLL, 97 (45%) were receiving CLL-directed treatment at diagnosis of COVID-19: 29% Bruton tyrosine kinase inhibitor (BTKi), 16% chemoimmunotherapy (CIT), 11% Bcl-2 inhibitor, and 4% phosphoinositide 3-kinase inhibitor. Regarding the severity of COVID-19, 60% pts required admission to the hospital, 21% pts were admitted to the intensive care unit (ICU), and 12% received invasive mechanical ventilation. The overall case fatality rate was 28%. Major comorbidities, age over 72, male gender, CLL treatment in history, CLL-directed treatment at COVID-19 diagnosis were associated with increased risk of death. Of note, concurrent therapy with BTKi compared to CIT was not associated with better outcome of COVID-19.

Prognostic Impact of Organomegaly in Mastocytosis: An Analysis of the European Competence Network on Mastocytosis.

BACKGROUND: Organomegaly, including splenomegaly, hepatomegaly, and/or lymphadenopathy, are important diagnostic and prognostic features in patients with cutaneous mastocytosis (CM) or systemic mastocytosis (SM). OBJECTIVES: To investigate the prevalence and prognostic impact of 1 or more organomegalies on clinical course and survival in patients with CM/SM. METHODS: Therefore, 3155 patients with CM (n = 1002 [32%]) or SM (n = 2153 [68%]) enrolled within the registry of the European Competence Network on Mastocytosis were analyzed. RESULTS: Overall survival (OS) was adversely affected by the number of organomegalies (OS: #0 vs #1 hazard ratio [HR], 4.9; 95% CI, 3.4-7.1, P < .001; #1 vs #2 HR, 2.1, 95% CI, 1.4-3.1, P < .001; #2 vs #3 HR, 1.7, 95% CI, 1.2-2.5, P = .004). Lymphadenopathy was frequently detected in patients with smoldering SM (SSM, 18 of 60 [30%]) or advanced SM (AdvSM, 137 of 344 [40%]). Its presence confered an inferior outcome in patients with AdvSM compared with patients with AdvSM without lymphadenopathy (median OS, 3.8 vs 2.6 years; HR, 1.6; 95% CI, 1.2-2.2; P = .003). OS was not different between patients having organomegaly with either ISM or SSM (median, 25.5 years vs not reached; P = .435). At time of disease progression, a new occurrence of any organomegaly was observed in 17 of 40 (43%) patients with ISM, 4 of 10 (40%) patients with SSM, and 33 of 86 (38%) patients with AdvSM, respectively. CONCLUSIONS: Organomegalies including lymphadenopathy are often found in SSM and AdvSM. ISM with organomegaly has a similar course and prognosis compared with SSM. The number of organomegalies is adversely associated with OS. A new occurrence of organomegaly in all variants of SM may indicate disease progression.

Mast cell leukemia: clinical and molecular features and survival outcomes of patients in the ECNM Registry.

Mast cell leukemia (MCL) is a rare subtype of systemic mastocytosis defined by ≥20% mast cells (MC) on a bone marrow aspirate. We evaluated 92 patients with MCL from the European Competence Network on Mastocytosis registry. Thirty-one (34%) patients had a diagnosis of MCL with an associated hematologic neoplasm (MCL-AHN). Chronic MCL (lack of C-findings) comprised 14% of patients, and only 4.5% had "leukemic MCL" (≥10% circulating MCs). KIT D816V was found in 62/85 (73%) evaluable patients; 9 (11%) individuals exhibited alternative KIT mutations, and no KIT variants were detected in 14 (17%) subjects. Ten evaluable patients (17%) had an abnormal karyotype and the poor-risk SRSF2, ASXL1, and RUNX1 (S/A/R) mutations were identified in 16/36 (44%) patients who underwent next-generation sequencing. Midostaurin was the most common therapy administered to 65% of patients and 45% as first-line therapy. The median overall survival (OS) was 1.6 years. In multivariate analysis (S/A/R mutations excluded owing to low event rates), a diagnosis of MCL-AHN (hazard ratio [HR], 4.7; 95% confidence interval [CI], 1.7-13.0; P = .001) and abnormal karyotype (HR, 5.6; 95% CI, 1.4-13.3; P = .02) were associated with inferior OS; KIT D816V positivity (HR, 0.33; 95% CI, 0.11-0.98; P = .04) and midostaurin treatment (HR, 0.32; 95% CI, 0.08-0.72; P = .008) were associated with superior OS. These data provide the most comprehensive snapshot of the clinicopathologic, molecular, and treatment landscape of MCL to date, and should help further inform subtyping and prognostication of MCL.

Secondary malignancies and survival of FCR-treated patients with chronic lymphocytic leukemia in Central Europe.

This is the first large-scale cross-country analysis of patients with chronic lymphocytic leukemia (CLL) aimed to evaluate the incidence, types, and key prognostic factors of secondary malignancies, and to assess the impact on overall survival based on retrospective claims data from three Central European countries. We analyzed 25,814 newly diagnosed CLL patients from Czechia, Hungary, and Poland; 10,312 (39.9%) patients were treated for CLL in study periods between 2004 and 2016. Out of the treated patients, 1986 (19.3%) received the FCR therapy in the first line and 779 (7.6%) received FCR in subsequent lines. We observed that 33.7% of treated patients developed secondary malignancies during the study. Based on country estimates, the probability to develop a secondary malignancy within 4 years since starting the first-line FCR therapy ranged between 28.0% and 36.8%. We found the age at diagnosis, male gender, any malignancy prior to the CLL diagnosis, and the CLL treatment to be the key risk factors for developing secondary malignancies. Specifically, the FCR therapy was a statistically significant (p < 0.001) prognostic factor for risk increase with the hazard ratio between 1.46 and 1.60. Across the three Central European countries, we observed consistent results indicating FCR increased the risk of secondary malignancies in CLL patients. We conclude that secondary malignancies are clearly an undervalued burden for CLL patients, caregivers, and the healthcare system. When evaluating new therapies in regulatory and reimbursement decision making, the factor of secondary malignancies deserves deeper considerations.

Differential diagnosis of leukocytosis and leukopenia.

The blood cell count is often examined in routine clinical praxis. Physiologic leucocyte count is in range 4-10 × 109 in liter of blood. Abnormal values of leukocytes and subtypes of leukocytes in differential count are often present. Changes in leukocytes counts are caused by variety of benignant or malignant conditions. It is important in clinical praxis to interpret changes in blood cell count correctly and choose adequate approach in investigation process. In general, leukocytosis and leukocytopenia may present in primary hematologic disorder or secondary/reactive states, caused by reaction of hematopoiesis to underlying condition. This article review common causes of leukocytosis or leucopenia and give basic advice how to investigate patients with changes in leukocytes count.

Thrombotic and bleeding complications in patients with chronic lymphocytic leukemia and severe COVID-19: a study of ERIC, the European Research Initiative on CLL.

BACKGROUND: Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to COVID-19 related poor outcomes, including thrombosis and death, due to the advanced age, the presence of comorbidities, and the disease and treatment-related immune deficiency. The aim of this study was to assess the risk of thrombosis and bleeding in patients with CLL affected by severe COVID-19. METHODS: This is a retrospective multicenter study conducted by ERIC, the European Research Initiative on CLL, including patients from 79 centers across 22 countries. Data collection was conducted between April and May 2021. The COVID-19 diagnosis was confirmed by the real-time polymerase chain reaction (RT-PCR) assay for SARS-CoV-2 on nasal or pharyngeal swabs. Severe cases of COVID-19 were defined by hospitalization and the need of oxygen or admission into ICU. Development and type of thrombotic events, presence and severity of bleeding complications were reported during treatment for COVID-19. Bleeding events were classified using ISTH definition. STROBE recommendations were used in order to enhance reporting. RESULTS: A total of 793 patients from 79 centers were included in the study with 593 being hospitalized (74.8%). Among these, 511 were defined as having severe COVID: 162 were admitted to the ICU while 349 received oxygen supplementation outside the ICU. Most patients (90.5%) were receiving thromboprophylaxis. During COVID-19 treatment, 11.1% developed a thromboembolic event, while 5.0% experienced bleeding. Thrombosis developed in 21.6% of patients who were not receiving thromboprophylaxis, in contrast to 10.6% of patients who were on thromboprophylaxis. Bleeding episodes were more frequent in patients receiving intermediate/therapeutic versus prophylactic doses of low-molecular-weight heparin (LWMH) (8.1% vs. 3.8%, respectively) and in elderly. In multivariate analysis, peak D-dimer level and C-reactive protein to albumin ratio were poor prognostic factors for thrombosis occurrence (OR = 1.022, 95%CI 1.007‒1.038 and OR = 1.025, 95%CI 1.001‒1.051, respectively), while thromboprophylaxis use was protective (OR = 0.199, 95%CI 0.061‒0.645). Age and LMWH intermediate/therapeutic dose administration were prognostic factors in multivariate model for bleeding (OR = 1.062, 95%CI 1.017-1.109 and OR = 2.438, 95%CI 1.023-5.813, respectively). CONCLUSIONS: Patients with CLL affected by severe COVID-19 are at a high risk of thrombosis if thromboprophylaxis is not used, but also at increased risk of bleeding under the LMWH intermediate/therapeutic dose administration.

Duplication of 8q24 in Chronic Lymphocytic Leukemia: Cytogenetic and Molecular Biologic Analysis of MYC Aberrations.

Chronic lymphocytic leukemia (CLL) with cytogenetics findings, such as complex karyotype and deletions of TP53 or ATM, is associated with adverse clinical outcomes. Additional chromosomal abnormalities further stratify patients into groups with diverse prognoses. Gain of 8q24 is one of the abnormalities considered as prognostically unfavorable. In our study, we performed a FISH analysis in an initial cohort of 303 consecutive CLL patients and determined the frequency of +8q to be 6.3 %. Our analysis confirmed the association with TP53/ATM aberrations and CK, as the frequency of +8q reached 26.7 % in an extended delTP53/ATM+CK cohort. M-FISH analysis enabled the identification of partner chromosomes where the segment of the duplicated 8q arm was localized. More detailed mapping of the gained 8q region using the M-BAND method determined the smallest amplified region 8q23-8qter. We observed significantly shorter overall survival (OS; 9.0 years in +8q-positive vs. 10.6 years in +8q-negative; p=0.02) and detected slightly higher MYC mRNA/protein levels in +8q-positive vs. +8q-negative patients.