Chronic myelomonocytic leukemia: 2018 update on diagnosis, risk stratification and management

Cytotoxicity of sub-lethal doses of vanadium pentoxide in male Oryctolagus cuniculus

Vanadium pentoxide (V2O5) is one of the compounds that have been reported to pose varying degrees of toxicity upon exposure; thus, making it a challenging environmental hazard that affects living organisms. This study investigated the cytotoxicity effects of daily sub-lethal oral doses of V2O5 on the bone marrow of male Oryctolagus cuniculus after 21 days. Male O. cuniculus (n = 60, ∼ 6 week old, 433.45 ± 5.00 g body weight) were simply randomized into four experimental groups and a control with three replicates of four animals each. Based on the estimated 96-h LD50 value of 119.0 mg/kg, sub-lethal doses of V2O5 were prepared as 1 mg/kg, 5 mg/kg, 10 mg/kg and 20 mg/kg, and administered to the test animals daily by oral gavage for 21 days. Vanadium pentoxide induced cytotoxicity in the bone marrow cells (BMCs) of exposed groups, with significant changes in all evaluated haemopoietic bone marrow stem cells (erythrocytes, leukocytes, thrombocytes and plasma cells). There were mixed trends in the values of leucocyte differentials in the exposed animal. Oral exposure to V2O5 exerts cytopathologic effects in the forms of DNA damage on the bone marrow of O. cuniculus. These findings support previous reports on the environmental hazards vanadium pentoxide poses to living organisms.

Survival Outcomes of U.S. Patients with CMML: A Two-Decade Analysis from the SEER Database

Background: Chronic Myelomonocytic Leukemia (CMML) is a rare and aggressive form of leukemia with characteristics of both myeloproliferative neoplasms (MPNs) and myelodysplastic syndromes (MDSs). This study aims to explore the clinical features, survival outcomes, and prognostic factors in CMML patients over the past 20 years using a large sample. Methods: The study data from 4124 patients diagnosed with CMML between 2000 and 2017 were sourced from the SEER database. Demographic and clinical characteristics, along with overall and cancer-specific mortality, were examined. Factors with a p-value < 0.01 in univariate Cox regression were included in the multivariate Cox model to identify independent prognostic factors, with hazard ratios (HRs) greater than one indicating adverse outcomes. Results: The majority of the cohort were male (61.57%), and most diagnoses occurred between ages 60-79 (55.16%), with a small percentage under 40 (1.41%). Non-Hispanic whites represented the largest racial group (79.03%). Multivariate analysis showed higher mortality in males, those aged 80+, residents in metropolitan areas with populations between 250,000 and 1 million, single or widowed individuals, and those who underwent chemotherapy. Conversely, lower mortality was associated with an annual income of $75,000+. Conclusions: CMML remains a rare and highly aggressive hematologic disorder. This U.S.-based retrospective cohort study identified male gender, advanced age, single or widowed status, and chemotherapy as independent poor prognostic factors. While it is expected that older patients and those requiring chemotherapy would have a poorer prognosis, the higher mortality risk in single or widowed patients, as well as males, warrants further investigation. The early involvement of family and community support may help reduce mortality in these groups, suggesting a need for larger prospective studies to explore these associations further.

Chronic myelomonocytic leukemia primarily presenting as life-threatening pericardial effusion, Eldoret, Kenya: A case report

Key Clinical Message

Chronic myelomonocytic leukemia, a rare case of hematological malignancy mainly affects the elderly and may present with life threatening pericardial effusion as an initial manifestation. High index of suspicion is hence key for early management.

Abstract

We present a case of an 81-year-old African male who presented with progressive cough, respiratory distress and bilateral lower limb swelling, and was diagnosed with life-threatening pericardial effusion resulting from chronic myelomonocytic leukemia following complete blood count, peripheral blood film, bone marrow aspirate with trephine biopsy, and flow cytometry studies.

Chronic myelomonocytic leukemia: 2024 update on diagnosis, risk stratification and management

DISEASE OVERVIEW

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes and myeloproliferative neoplasms, characterized by prominent monocytosis and an inherent risk for leukemic transformation (~15%-20% over 3-5 years).

DIAGNOSIS

Newly revised diagnostic criteria include sustained (>3 months) peripheral blood (PB) monocytosis (≥0.5 × 109/L; monocytes ≥10% of leukocyte count), consistent bone marrow (BM) morphology, <20% BM or PB blasts (including promonocytes), and cytogenetic or molecular evidence of clonality. Cytogenetic abnormalities occur in ~30% of patients, while >95% harbor somatic mutations: TET2 (~60%), SRSF2 (~50%), ASXL1 (~40%), RAS pathway (~30%), and others. The presence of ASXL1 and DNMT3A mutations and absence of TET2 mutations negatively impact overall survival (ASXL1WT/TET2MT genotype being favorable).

RISK STRATIFICATION

Several risk models serve similar purposes in identifying high-risk patients that are considered for allogeneic stem cell transplant (ASCT) earlier than later. Risk factors in the Mayo Molecular Model (MMM) include presence of truncating ASXL1 mutations, absolute monocyte count >10 × 109/L, hemoglobin <10 g/dL, platelet count <100 × 109/L, and the presence of circulating immature myeloid cells; the resulting 4-tiered risk categorization includes high (≥3 risk factors), intermediate-2 (2 risk factors), intermediate-1 (1 risk factor), and low (no risk factors); the corresponding median survivals were 16, 31, 59, and 97 months. CMML is also classified as being "myeloproliferative (MP-CMML)" or "myelodysplastic (MD-CMML)," based on the presence or absence of leukocyte count of ≥13 × 109/L.

TREATMENT

ASCT is the only treatment modality that secures cure or long-term survival and is appropriate for MMM high/intermediate-2 risk disease. Drug therapy is currently not disease-modifying and includes hydroxyurea and hypomethylating agents; a recent phase-3 study (DACOTA) comparing hydroxyurea and decitabine, in high-risk MP-CMML, showed similar overall survival at 23.1 versus 18.4 months, respectively, despite response rates being higher for decitabine (56% vs. 31%).

UNIQUE DISEASE ASSOCIATIONS

These include systemic inflammatory autoimmune diseases, leukemia cutis and lysozyme-induced nephropathy; the latter requires close monitoring of renal function during leukocytosis and is a potential indication for cytoreductive therapy.

Kidney and Urinary Tract Involvement in Chronic Myelomonocytic Leukemia

Chronic myelomonocytic leukemia (CMML) is a hematologic malignancy affecting the bone marrow and resulting in peripheral blood monocytosis. Kidney and urinary tract involvement is common and can present dramatically with life-threatening consequences. Kidney involvement can be the result of direct or indirect mechanisms, including prerenal azotemia, glomerular disease, tubulointerstitial involvement, and renovascular disorders. Urinary tract involvement, electrolyte and acid-base disorders, as well as nephrotoxicity from treatment of the disorder can also occur. Given this multifactorial pathogenesis involving several mechanisms concomitantly, nephrologists must exercise heightened awareness and maintain a low threshold for kidney biopsy. There is a pressing need for future research endeavors to elucidate and target the manifestations of CMML that involve the kidneys with the ultimate goal of augmenting overall prognosis and therapeutic outcomes.

NLRP3 inflammasome activation and symptom burden in KRAS-mutated CMML patients is reverted by IL-1 blocking therapy

Chronic myelomonocytic leukemia (CMML) is frequently associated with mutations in the rat sarcoma gene (RAS), leading to worse prognosis. RAS mutations result in active RAS-GTP proteins, favoring myeloid cell proliferation and survival and inducing the NLRP3 inflammasome together with the apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), which promote caspase-1 activation and interleukin (IL)-1β release. Here, we report, in a cohort of CMML patients with mutations in KRAS, a constitutive activation of the NLRP3 inflammasome in monocytes, evidenced by ASC oligomerization and IL-1β release, as well as a specific inflammatory cytokine signature. Treatment of a CMML patient with a KRASG12D mutation using the IL-1 receptor blocker anakinra inhibits NLRP3 inflammasome activation, reduces monocyte count, and improves the patient's clinical status, enabling a stem cell transplant. This reveals a basal inflammasome activation in RAS-mutated CMML patients and suggests potential therapeutic applications of NLRP3 and IL-1 blockers.

Targeted NGS on sequential bone marrow biopsies aids in the evaluation of cytopenias and monocytosis and documents clonal evolution-a proof of principle study

Differential diagnosis of clonal versus reactive cytopenia and monocytosis, respectively, frequently presents a diagnostic challenge. With the two recent classifications of myeloid disorders, mutational analysis has gained importance as a diagnostic tool. However, reports on its utility on trephine bone marrow biopsies (BMB) are sparse. The aim of our proof of principle study was to determine the suitability of targeted sequencing for the longitudinal evaluation of cytopenia and monocytosis and demonstration of clonal evolution on sequential BMB. Seventy-seven EDTA-decalcified BMB of 33 patients with peripheral cytopenia and/or monocytosis, including at least one follow-up biopsy/patient, were included. Initial morphological diagnoses were idiopathic cytopenia of undetermined significance (ICUS, 8 cases), MDS (without blast increase, 7 cases), MDS with increased blasts/excess blasts (MDS-IB/EB) (11 cases), and CMML (7 cases). Thirty-one genes relevant for myeloid disorders were examined using two custom AmpliSeq NGS panels. Mutations were found in the initial BMB of 5/8 cases of ICUS, thus changing the diagnosis to clonal cytopenia of unknown significance (CCUS), 5/7 MDS, 10/11 MDS-IB/EB, and 7/7 CMML. Clonal evolution was observed in 14/33 (42%) cases, mostly associated with disease progression. None of the wild-type patients acquired mutations during follow-up. NGS-based mutation profiling is a robust diagnostic tool for BMB and provides valuable additional information, especially for cases with no/minimal dysplasia, and for better risk stratification of MDS. Tracking variant allele frequency and appearance of mutations over time allows for observing clonal evolution or relapse.

Germline CSF3R Variant in Chronic Myelomonocytic Leukemia: Linking Genetic Predisposition to Uncommon Hemorrhagic Symptoms

Chronic myelomonocytic leukemia (CMML) is a hematological neoplasm characterized by monocytosis, splenomegaly, thrombocytopenia, and anemia. Moreover, it is associated with SRSF2 mutations and, rarely, with CSF3R variants. We present the case of an 84-year-old patient with persistent anemia and monocytosis. Due to the presence of dysmorphic granulocytes, monocyte atypia, and myeloid precursors in the peripheral blood cells, the patient was subjected to a bone marrow examination. The diagnosis was consistent with CMML type 2. The Hemocoagulative test showed an increase in fibrinolysis markers. Next-generation targeted sequencing showed TET2 and SRSF2 mutations, along with an unexpected CSF3R germline missense variant, rarely encountered in CMML. The patient started Azacitidine treatment and achieved normal hemostatic process values. In conclusion, we identified a heterozygous germline mutation that, together with TET2 and SRSF2 variants, was responsible for the hemorrhagic manifestation.

Evaluation and validation of the prognostic value of platelet indices in patients with leukemia

Platelets (PLTs) are believed to play a role in the process by which tumors can accelerate their growth rate, as well as offer the physical and mechanical support necessary to evade the immunological system and metastasis. There is, however, no literature available if PLTs have a role in leukemia. It is significant for PLTs to play a part in hematological malignancies from a therapeutic standpoint and to have the capacity to serve as a prognostic marker in the evolution of leukemia. This is because PLTs play a crucial role in the development of cancer and tumors. In this study, it will be shown that PLT count can be used to predict long-term prognosis after chemotherapy especially in the case of acute myeloid leukemia patients. Furthermore, low PLT-to-lymphocyte ratio and mean PLT volume, as well as high PLT distribution width, are associated with poor prognosis and may represent a novel independent prognostic factor.

An unusual response to 5-azacitidine by a patient with chronic myelomonocytic leukemia

Key Clinical Message

Hypomethylating agents may be useful in some but not all cases of myelodysplastic syndromes. In some versions of these conditions, this treatment may yield deleterious results.

Abstract

Chronic myelomonocytic leukemia (CMML) is considered to be a heterogeneous group of hematopoietic neoplasms. Usually it shares the features of myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) and is known as MDS/MPN. It occurs mostly in the elderly and has an inherent tendency to transform to acute myeloid leukemia. FDA has approved hypomethylating agents (HMAs) such as 5-azacitidine (AZA) and decitabine (DEC) for the treatment of this disorder. The extent of response rate to AZA varies considerably among patients. Our report describes a patient with CMML who not only did not respond to a conventional dose of intravenous (IV) therapy with AZA, but showed marked progression of the disease with the leucocyte count rising exponentially while undergoing the aforesaid treatment. We believe this is the first such case reported in the currently extant literature.

Updates in molecular genetics of therapy-related myeloid neoplasms

Therapy-related myeloid neoplasms (t-MN) are a heterogeneous group of aggressive myeloid neoplasms that arise following exposure to various cytotoxic therapeutic agents and/or ionizing radiation for treatment of prior non-myeloid malignancy or autoimmune disease. Each therapeutic group has been associated with varying latency intervals from the time of therapy exposure to onset of t-MN, as well as certain recurrent genetic alterations. This review will focus on the molecular genetic alterations that have been described in t-MNs, as well as recent updates regarding diagnostic classification.

Monocytosis in primary care and risk of haematological malignancies

Monocytosis (≥0.5 × 10⁹ /L in peripheral blood) is the hallmark of chronic myelomonocytic leukaemia (CMML) but may be present in a spectrum of diseases including other haematological malignancies. In the primary care sector, monocytosis is a relatively common finding, but its predictive value for haematological malignancy is unknown. We included 663 184 adult primary care patients from the greater Copenhagen area with one or more differential cell counts registered between 2000 and 2016 and followed them in the extensive nationwide Danish health data registers for 3 years after blood sampling. We used logistic regression to model the risk of haematological malignancy and death following monocytosis. Monocytosis was associated with an increased risk of all types of haematological malignancy with the greatest relative risk increase observed in CMML with an OR of 105.22 (95% confidence interval: 38.27-289.30). Sustained monocytosis (at least two requisitions in 3 months) further increased CMML risk, although the diagnosis was still very rare, that is, observed in only 0.1% of these individuals. Outside the haematological setting, the absolute risk of haematological malignancy associated with monocytosis is low and haematological malignancy should mainly be suspected when monocytosis is sustained or the clinical presentation raises suspicion of malignancy.

A retrospective study of cladribine and low-dose cytarabine-based regimens for the treatment of chronic myelomonocytic leukemia and secondary acute myeloid leukemia

BACKGROUND

Patients with higher risk chronic myelomonocytic leukemia (CMML) have limited therapeutic options beyond hydroxyurea and hypomethylating agents (HMAs). Regimens based on a backbone of cladribine (CLAD), low-dose cytarabine (LDAC), and an HMA are effective low-intensity therapies for acute myeloid leukemia (AML).

METHODS

The authors conducted a retrospective chart review to evaluate the efficacy of CLAD/LDAC/HMA in CMML and secondary acute myeloid leukemia (sAML) arising from CMML. Responses were evaluated according to the 2006 International Working Group criteria for CMML and the 2017 European LeukemiaNet criteria for AML. The overall survival (OS), leukemia-free survival (LFS), and duration of response were evaluated with the Kaplan-Meier method. Patients were stratified on the basis of prior HMA exposure.

RESULTS

The authors identified 21 patients with CMML (eight with HMA-naive CMML and 13 with HMA-failure CMML) and 33 patients with sAML (11 with HMA-naive sAML and 22 with HMA-failure sAML) treated with CLAD/LDAC/HMA-based regimens. The CMML cohort was enriched for high-risk features (proliferative type, elevated blasts, and RAS/MAPK mutations). The overall response rate was 33% in CMML (50% in HMA-naive CMML and 23% in HMA-failure CMML) and 48% in sAML (82% in HMA-naive sAML and 32% in HMA-failure sAML). The median OS was 14.4, 8.8, 42.9, and 2.9 months for HMA-naive CMML, HMA-failure CMML, HMA-naive sAML, and HMA-failure sAML, respectively. The median LFS was 14.4 and 3.9 months for HMA-naive CMML and HMA-failure CMML, respectively.

CONCLUSIONS

CLAD/LDAC/HMA-based regimens are effective in a subset of patients with higher risk CMML and sAML arising from CMML who have not previously experienced HMA failure. These findings must be confirmed in prospective studies.

Chronic myelomonocytic leukemia in a 72-year-old male from Nepal: A case report

Chronic myelomonocytic leukemia (CMML) is a rare disease of clonal hematopoietic stem cells with an inherent risk of leukemic transformation, seen in an elderly male.

Case Presentation

Herein, the authors report a case of CMML in a 72-year-old male who presented with fever and abdominal pain for 2 days with a history of easy fatigability. Examination revealed pallor and palpable supraclavicular nodes. Investigations showed leukocytosis with a monocyte count of 22% of white blood cell count, 17% blast cells in bone marrow aspiration, increased blast/promonocytes, and positive markers in immunophenotyping. The patient is planned for injection of azacitidine, 7 days cycle for a total of six cycles.

Clinical Discussion

CMML is classified as overlapping myelodysplastic/myeloproliferative neoplasms. It can be diagnosed based on a peripheral blood smear, bone marrow aspiration and biopsy, chromosomal analysis, and genetic tests. The commonly used treatment options are hypomethylating agents like azacitidine and decitabine, allogeneic hematopoietic stem cell transplant, and cytoreductive agents like hydroxyurea.

Conclusion

Despite various treatment options, the treatment is still unsatisfactory, demanding standard management strategies.

Biallelic TET2 mutations and canonical ASXL1 mutations are frequent and cooccur in Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN): An institutional experience and review of literature

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is recurrently mutated in epigenetic pathway genes. We studied the myeloid-related genetic mutations in a cohort of five patients with BPDCN and one paired relapse case at our institution and identified a high frequency of biallelic TET2 and canonical ASXL1 (c.1934dupG) mutations. The number of cases is small, but the variant allele fraction (VAF) sums of the TET2 mutations, as well as the persistence of TET2 mutations in a case of relapsed BPDCN, suggest an ancestral/founder nature of TET2 clones in the cases. Further literature review shows a high frequency of biallelic TET2 mutations in reported cases of BPDCN.

Srsf2P95H/+ co-operates with loss of TET2 to promote myeloid bias and initiate a chronic myelomonocytic leukemia-like disease in mice

Recurrent mutations in RNA splicing proteins and epigenetic regulators contribute to the development of myelodysplastic syndrome (MDS) and related myeloid neoplasms. In chronic myelomonocytic leukemia (CMML), SRSF2 mutations occur in ~50% of patients and TET2 mutations in ~60%. Clonal analysis indicates that either mutation can arise as the founder lesion. Based on human cancer genetics we crossed an inducible Srsf2P95H/+ mutant model with Tet2fl/fl mice to mutate both concomitantly in hematopoietic stem cells. At 20-24 weeks post mutation induction, we observed subtle differences in the Srsf2/Tet2 mutants compared to either single mutant. Under conditions of native hematopoiesis with aging, we see a distinct myeloid bias and monocytosis in the Srsf2/Tet2 mutants. A subset of the compound Srsf2/Tet2 mutants display an increased granulocytic and distinctive monocytic proliferation (myelomonocytic hyperplasia), with increased immature promonocytes and monoblasts and binucleate promonocytes. Exome analysis of progressed disease demonstrated mutations in genes and pathways similar to those reported in human CMML. Upon transplantation, recipients developed leukocytosis, monocytosis, and splenomegaly. We reproduce Srsf2/Tet2 co-operativity in vivo, yielding a disease with core characteristics of CMML, unlike single Srsf2 or Tet2 mutation. This model represents a significant step toward building high fidelity and genetically tractable models of CMML.

Treatment Outcomes and Prognostic Factors in 66 Patients with Chronic Myelomonocytic Leukemia (CMML) in a Single Center

INTRODUCTION

Chronic myelomonocytic leukemia (CMML) is a rare hematological malignancy bearing of both myelodysplastic syndrome and myeloproliferative neoplasm characteristics. Despite the low incidence, the clinical diagnosis of CMML was difficult and the survival was poor. The optimal first-line therapy for CMML still remains a matter of debate.

METHODS

We retrospectively analyzed the clinical characteristics of 66 CMML patients in a single center during the past 10 years and studied the survival status of CMML patients in the real world and the influence of treatment methods on the prognosis of patients.

RESULTS

For the 66 CMML patients, the median age was 60 years old (IQR 47.0-67.0), and an approximately 1.6:1.0 male-to-female ratio was found. CMML-0, CMML-1 and CMML-2 accounted for 13.7% (9/66), 43.9% (29/66) and 42.4% (28/66), respectively. The chromosome abnormality rate was 27.2% (18/66). Gene mutation was detected in 60 patients by sequenced in first-generation with 51.1% (22/43) gene mutations and in NGS with 82.3% (14/17) gene mutations. The top three mutation genes were ASXL1MT (11/60, 18.3%), TET2MT (10/60, 16.7%), and SRSF2 MT (9/60, 15.0%). There were 27 patients in supportive therapy group, and 39 patients in chemotherapy group including patients undergoing HSCT. Patients in chemotherapy group showed better OS than those in the supportive group before and after PSM analysis with p < 0.05. Patients with blast cell in bone marrow ≥10% or WHO CMML-2 benefited more from chemotherapy treatment achieving better OS. Multivariate analysis showed that supportive therapy and intermediate-2/high in CPSS were independent risk factors for OS after PSM.

DISCUSSION

Chemotherapy including hypomethylating agents prolonged overall survival of CMML patients, especially in patients with blast cell ≥10% in bone marrow or WHO CMML-2 comparing with supportive therapy. Sequencing may provide direct insight into the molecular mechanism by detection of gene mutation, enabling personalized treatment in the future.

[Incidence and clinical significance of platelet transfusion refractoriness after allogeneic hematopoietic stem cell transplantation in patients with chronic myelomonocytic leukemia]

Objective: To retrospectively analyze the incidence and clinical significance of platelet transfusion refractoriness (PTR) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with chronic myelomonocytic leukemia (CMML) . Methods: A cohort of 55 CMML patients received allo-HSCT at Peking University Institute of Hematology during 2004-2021 were retrospectively assessed. The incidence of PTR within 30 days after allo-HSCT was retrospectively analyzed, and the impact on clinical outcomes and bleeding event were compared between patients with platelet transfusion refractoriness (PTR) or effective platelet transfusion (EPT) . Results: The incidence of PTR after allo-HSCT in CMML patients was 25.5% (14/55) . PTR patients had a lower rate of platelet engraftment than EPT patients (28.6% vs 100%) , and the median time of engraftment was 67 (33-144) days and 21 (9-157) days respectively (P<0.010) . There was no significant difference between two groups in acute graft-versus-host disease (aGVHD) and chronic graft-versus-host disease (cGVHD) (P=0.183, P=0.455) . After following-up a median of 684 (24-3978) days, the 1-year overall survival (OS) and 1-year leukemia free survival (LFS) in PTR and EPT patients were (35.4±13.9) % vs (75.1±7.8) % (P=0.037) and (28.1±13.3) % vs (65.3±8.2) % (P=0.072) , respectively. The transplant-related mortality (TRM) were (48.2±2.4) % and (9.0±0.25) %, respectively (P=0.009) . Bleeding events occurred in five patients (35.7%) of PTR and 2 patients (4.9%) of EPT (P=0.009) . Conclusion: In CMML patients with allo-HSCT, the incidence of PTR is 25.5%, which was associated with delayed platelet engraftment, increased bleeding events, inferior OS and increased TRM.

Chronic myelomonocytic leukemia: 2022 update on diagnosis, risk stratification, and management

DISEASE OVERVIEW

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes and myeloproliferative neoplasms, with an inherent risk for leukemic transformation (~15% over 3-5 years).

DIAGNOSIS

Diagnosis is based on the presence of sustained (>3 months) peripheral blood monocytosis (≥1 × 10⁹ /L; monocytes ≥10%), usually with accompanying bone marrow dysplasia. Clonal cytogenetic abnormalities occur in ~30% of patients, while >90% have somatic gene mutations. Mutations involving TET2 (~60%), SRSF2 (~50%), ASXL1 (~40%), and the oncogenic RAS pathway (~30%) are frequent, while the presence of ASXL1 and DNMT3A mutations and the absence of TET2 mutations negatively impact overall survival.

RISK-STRATIFICATION

Molecularly integrated prognostic models include the Groupe Français des Myélodysplasies, Mayo Molecular Model (MMM), and the CMML specific prognostic model. Risk factors incorporated into the MMM include presence of truncating ASXL1 mutations, absolute monocyte count >10 × 10⁹ /L, hemoglobin <10 g/dL, platelet count <100 × 10⁹ /L, and the presence of circulating immature myeloid cells. The MMM stratifies CMML patients into four groups: high (≥3 risk factors), intermediate-2 (2 risk factors), intermediate-1 (1 risk factor), and low (no risk factors), with median survivals of 16, 31, 59, and 97 months, respectively.

RISK-ADAPTED THERAPY

Hypomethylating agents such as 5-azacitidine and decitabine are commonly used, with overall response rates of ~40%-50% and complete remission rates of ~7%-17%; with no impact on mutational allele burdens. Allogeneic stem cell transplant is the only potentially curative option but is associated with significant morbidity and mortality.

Coexistence of Chronic Myelomonocytic Leukemia and Ulcerative Colitis With Rapid Progression to Acute Myelomonocytic Leukemia: A Case Report

Chronic myelomonocytic leukemia (CMML) is a clonal myeloid neoplasm characterized by sustained peripheral blood monocytosis and variable dyspoiesis. We present a case of a 64-year-old male who presented with severe non-bloody diarrhea, peripheral blood neutrophilia, and monocytosis. He was diagnosed with myeloproliferative CMML type 0 and ulcerative colitis (UC). Next-generation DNA sequencing of a bone marrow sample demonstrated mutations of the TET2, ASXL1, NRAS, and SRSF2 genes along with low-level JAK2^V617F mutation. Both TET2 and SRSF2 mutations are associated with systemic inflammatory and autoimmune disease (SIAD), which includes UC. The patient's UC was managed successfully with vedolizumab infusions. The patient's concurrent CMML was monitored with a "wait and watch" approach. After five months, the patient asymptomatically tested positive for coronavirus disease 2019 (COVID-19). Seven months after his diagnosis of CMML, the patient presented in severe respiratory distress with acute left upper quadrant pain, splenomegaly, and multiorgan failure. A peripheral blood smear demonstrated marked leukocytosis (283 x 10^9 /L) with 39% blasts/promonocytes without Auer rods. The patient was diagnosed with acute myeloid leukemia with myelomonocytic features (AMML). In this report, we discuss the diagnosis of combined CMML and SIAD, mechanisms of immunoregulatory dysfunction that have been suggested to result in CMML progression, and the clinicopathologic significance of the patient's molecular abnormalities.

Real-world data on efficacy and safety of azacitidine therapy in chronic myelomonocytic leukemia in China: results from a multicenter, retrospective study

Chronic myelomonocytic leukemia (CMML) is a rare and aggressive myeloid malignancy with overlapped features of myelodysplastic syndromes/myeloproliferative neoplasms. Azacitidine (AZA), a hypomethylating agent, has been approved for the treatment of CMML in China, but real-world data are limited. Medical records of CMML patients who had received subcutaneously injected AZA were reviewed from January 2018 at five participating sites in China. Response was assessed according to the modified International Working Group (IWG 2006) criteria. Between January 2018 and November 2020, a total of 24 patients with CMML were included with a median age of 63 years. Patients received a median of 3 cycles of AZA treatment (range, 1-8). Overall response rate (ORR) was 37.5% (9 of 24); CR rate, PR rate, and mCR/HI rate were 8.3% (n = 2), 8.3% (n = 2), and 20.8% (n = 5), respectively. At a median duration of follow-up of 14.0 months (range 0.0-22.0 months), the median overall survival (OS) was 23.0 months. Univariate analysis revealed that ≥ 3 cycles of treatment was significantly associated with a higher 1-year OS rate compared with &lt; 3 cycles of AZA treatment. Treatment was generally well-tolerated. The most common (&gt; 10%) AEs were thrombocytopenia (n = 7, 29.2%), pneumonitis (n = 4, 16.7%) and fever (n = 3, 12.5%). This study provides valuable real-life data in China on the treatment schedules, efficacy and safety of AZA in the treatment of CMML.

Myeloproliferative Neoplasms with Monocytosis

PURPOSE OF REVIEW

Myeloproliferative neoplasms (MPN) are a heterogeneous group of hematopoietic stem cell neoplasms comprising of polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) that share driver mutations (JAK2/CALR/MPL) resulting in constitutive activation of JAK/STAT and other signaling pathways. Patients with MPN have shortened survival and an inherent risk for leukemic evolution. Prognostically relevant clinical and genetic parameters have been incorporated into mutation-enhanced scoring systems (MIPSS70-plus version 2.0, MIPSS-ET/PV). In the current review, we describe clinical and pathological features along with prognostic significance of MPN with monocytosis.

RECENT FINDINGS

Monocytosis, defined by an absolute monocyte count (AMC) ≥ 1 × 10 ⁹/L, is a typical manifestation of chronic myelomonocytic leukemia (CMML) but is also associated with 21% and 17% of PV and PMF patients, respectively. Recent studies on the subject have reported that MPN patients with monocytosis are older and present with concomitant leukocytosis. In regard to PV, patients with monocytosis harbor unfavorable cytogenetic abnormalities including +8, 7/7q, i(17q), 5/5q-,12p-, inv(3), or 11q23 rearrangement and SRSF2 mutations, whereas PMF patients with monocytosis had significant thrombocytopenia, higher circulating blasts, higher symptom burden, and ASXL1 mutations. Moreover, presence of monocytosis predicted inferior survival in both PV and PMF. Monocytosis in MPN is associated with a distinct clinical and genetic profile and may serve as a marker of aggressive disease biology.

The Use of an Interleukin-6 Inhibitor in Vasoplegic Shock from Severe Systemic Inflammatory Response Syndrome: A Case Report

A 66-year-old Caucasian male with a history of chronic myelomonocytic leukemia (CMML) developed fluid-unresponsive hypotension requiring initiation of four different maximum dosed vasopressors, steroids, and broad-spectrum antibiotics 4 hours following four-vessel coronary artery bypass grafting involving a 150-minute cardiac bypass. Placement of a Swanz-Ganz catheter showed a cardiac output of 7 L/minute with systemic vascular resistance of 571 dynes/sec/cm⁻⁵. Over 24 hours, three doses of tocilizumab (interleukin-6 inhibitor) every 8 hours were initiated, plus 250 mg methylprednisolone per 6 hours increment, and then daily thereafter. After the initial dose of tocilizumab, it was possible to wean vasoconstrictors. We have shown for the first time that therapy with tocilizumab is effective in reversing the hemodynamic instability associated with the significant systemic inflammatory response from the “double hit” of CMML and coronary artery bypass grafting with cardiopulmonary bypass as has previously been shown in cytokine release syndrome.

How to cite this article: Elkhatib WY, Saunders H, Helgeson SA, Moss JE. The Use of an Interleukin-6 Inhibitor in Vasoplegic Shock from Severe Systemic Inflammatory Response Syndrome: A Case Report. Indian J Crit Care Med 2021;25(8):939–941.

Mouse Models of CMML

Chronic myelomonocytic leukemia (CMML) is a rare and challenging type of myeloproliferative neoplasm. Poor prognosis and high mortality, associated predominantly with progression to secondary acute myeloid leukemia (sAML), is still an unsolved problem. Despite a growing body of knowledge about the molecular repertoire of this disease, at present, the prognostic significance of CMML-associated mutations is controversial. The absence of available CMML cell lines and the small number of patients with CMML make pre-clinical testing and clinical trials complicated. Currently, specific therapy for CMML has not been approved; most of the currently available therapeutic approaches are based on myelodysplastic syndrome (MDS) and other myeloproliferative neoplasm (MNP) studies. In this regard, the development of the robust CMML animal models is currently the focus of interest. This review describes important studies concerning animal models of CMML, examples of methodological approaches, and the obtained hematologic phenotypes.

IRF8 is a Reliable Monoblast Marker for Acute Monocytic Leukemias

Blast evaluation in patients with acute monocytic leukemias (AMoL) is notoriously difficult due to the lack of reliable surface markers and cytologic subtleties on the aspirate smears. While blasts of most nonmonocytic acute leukemias express CD34, available immunohistochemical antibodies to monocytic blasts also mark normal background mature monocytes. We searched for a potential biomarker candidate by surveying specific gene expression profiles of monocyte progenitors. Our investigations led us to IRF8, which is a lineage-specific transcription factor critical for the production of monocytic and dendritic cell progenitors. In this study, we tested and validated a monoclonal antibody to IRF8 as a novel immunohistochemical stain for trephine core biopsies of human bone marrow. We assessed the expression of IRF8 in 90 cases of AMoL, including posttherapy staging bone marrows, 23 cases of chronic myelomonocytic leukemia, 26 cases of other acute myeloid leukemia subtypes, and 18 normal control marrows. In AMoL, there was high correlation of IRF8-positive cells to aspirate blast count (R=0.95). Comparison of IRF8 staining to aspirate blast percentage in chronic myelomonocytic leukemia also showed good correlation (R=0.86). In contrast, IRF8-positive cells did not correlate with blast count in other subtypes of acute myeloid leukemia (R=0.56) and staining was <5% in all normal control marrows, even those with reactive monocytosis. We found that IRF8 was also weakly reactive in B cells and hematogones, with the latter accounting for rare cases of discrepancies. When IRF8 was used to categorize cases as AMoL, positive for residual leukemia or negative, the sensitivity was 98%, specificity was 82%, positive predictive value was 86%, and negative predictive value was 98%. These results demonstrate that IRF8 may serve as a clinically useful immunostain to diagnose and track AMoLs on bone marrow core biopsies. This can be particularly impactful in the setting of poor aspiration and focal blast increase. In the era of new targeted therapies that have been reported to induce monocytic outgrowths of leukemia, a marker for malignant monoblasts may prove even more critical.

Allogeneic Hematopoietic Stem Cell Transplantation for Chronic Myelomonocytic Leukemia: Clinical and Molecular Genetic Prognostic Factors in a Nordic Population

Chronic myelomonocytic leukemia (CMML) is an aggressive disease in which survival after allogeneic hematopoietic stem cell transplantation (HCT) remains relatively poor. An assessment of prognostic factors is an important part of treatment decision making and has the potential to be greatly improved by the inclusion of molecular genetics. However, there is a significant knowledge gap in the interpretation of mutational patterns. This study aimed to describe outcomes of allogeneic HCT in patients with CMML in relation to clinical and molecular genetic risk factors. This retrospective study included 64 patients with CMML who underwent allogeneic HCT between 2008 and 2018, with a median follow-up of 5.4 years. Next-generation sequencing using targeted myeloid panels was carried out on saved material from 51 patients from the time of transplantation. Kaplan-Meier and Cox regression were used for analysis of overall survival (OS), and cumulative incidence with competing risks and Fine and Gray models were used for analysis of relapse and nonrelapse mortality (NRM). Mutations were detected in 48 patients (94%), indicating high levels of minimal residual disease (MRD) positivity at transplantation, even among those in complete remission (CR) (n = 14), 86% of whom had detectable mutations. The most frequently mutated genes were ASXL1 (37%), TET2 (37%), RUNX1 (33%), SRSF2 (26%), and NRAS (20%). Risk stratification using the CMML-specific Prognostic Scoring System molecular score (CPSS-Mol) resulted in 45% of patients moving to a higher risk-group compared with risk stratification using the CPSS. High leucocyte count (≥13 × 10⁹/L), transfusion requirement, and previous intensive chemotherapy were associated with higher incidence of relapse. Being in CR was not linked to better outcomes. Neither ASXL1 nor RUNX1 mutation was associated with a difference in OS, relapse, or NRM, despite being high risk in the nontransplantation setting. TET2 mutations were associated with a significantly higher 3-year OS (73% versus 40%; P = .039). Achieving MRD-negative CR was rare in this CMML cohort, which may explain why we did not observe better outcomes for those in CR. This merits further investigation. Our analyses suggest that the negative impact of ASXL1 and RUNX1 mutations can be overcome by allogeneic HCT; however, risk stratification is complex in CMML and requires larger cohorts and multivariate models, presenting an ongoing challenge in this rare disease.

Cerebral localization of chronic myelomonocytic leukemia: a case report

BACKGROUND

Chronic myelomonocytic leukemia is a myelodysplastic/myeloproliferative neoplasm characterized by the infiltration of blood and bone marrow by immature monocytes. Cerebral localization of chronic myelomonocytic leukemia has never been described.

CASE PRESENTATION

We report the case of a Caucasian 59 year-old man with multiorgan chronic myelomonocytic leukemia infiltration, associated with uncommon brain involvement. There was no evidence of evolution to acute myeloid leukemia. The evidence of cerebral infiltration by chronic myelomonocytic leukemia was made after autopsy.

CONCLUSIONS

The fatal outcome of the patient raises the question of the potential benefit of early specific treatment, such as demethylating agents or intensive chemotherapy. Sharing such images of atypical and rapidly evolving chronic myelomonocytic leukemia and the disease history may help clinical decision-making in the future.

Hypomethylating agents in the treatment of chronic myelomonocytic leukemia: a meta-analysis and systematic review

OBJECTIVES

The present meta-analysis was performed to evaluate the efficacy, toxicities of both hypomethylating agents (decitabine and azaciticine) in the treatment of CMML patients.

METHODS

All available cohort studies of patients with CMML treated with decitabine and azacitidine were identified. The primary endpoints of this meta-analysis were response to hypomethylating agents. Pooled estimates of treatment response and drug-related adverse events were calculated using fixed or random effect models.

RESULTS

Fourteen studies with 600 CMML patients (decitabine: n=196; azacitidine: n=404) were identified and included for meta-analysis. HMAs yielded a pooled ORR estimate of 43% (95% CI: 36%-50%) in patients with CMML. Patients received either azacitidine or decitabine exhibited comparable incidence of ORR (43% vs. 45%, P=0.810), while significantly higher incidence of mCR was observed in patients treated with decitabine (23% vs. 10%, P=0.000). Decitabine treatment was also associated with higher incidence of transfusion independence (42% vs. 20%, P=0.044). Both HMAs led to objective hematologic or non-hematologic AEs (27%-43%), while dosage modification/delay were more frequent in patients treated with azacitidine (81% vs. 67%, P=0.021).

CONCLUSION

This current study may provide preliminary data in evaluating the efficacy and safety of HMAs in patients with CMML. Decitabine and azacitidine are comparable effective and safe in treating CMML. However, it is necessary to point out that any comparison of decitabine and azacitidine with respect to clinical outcomes can only be done in the context of a randomized controlled trial.

Study of the Chromosomal Abnormalities and Associated Complex Karyotypes in Hematological Cancer in the Population of West Bengal: A Prospective Observational Study

Introduction Chromosomal instability is an important feature of hematological cancer. The pathogenesis is complex and it involves genetic and epigenetic factors. As a genetic factor, chromosomal instability may play a key role in leukemogenesis. Accumulation of genetic alteration is mainly responsible for numerical and structural chromosomal rearrangement or clonal evaluation. But disease progression is often driven by chromosomal translocation, hyper- or hypodiploidy with structural abnormalities, and complex karyotypes.

Objective This research aimed to study the different types of chromosomal abnormalities in clinically suspected hematological cancer patients.

Materials and Methods Cytogenetic analysis was performed based on phytohemaglutinin stimulated peripheral blood lymphocyte cultures and bone marrow culture, without mitogen, of the respective patients of West Bengal from March 2016 to February 2018. All clinically suspected hematological cancer patients referred for karyotyping to the institutional genetics department have been included without any biasness of sex and age. Karyotypes were described according to the International System for Cytogenetic Nomenclature (ISCN 2005).

Results In the present study, 56 clinically suspected hematological cancer cases were observed and 41 cases of chromosomal rearrangement were found which clearly show chromosomal instability as the main driving force for hematological cancer transformation. Presence of variant Philadelphia chromosomes with classical translocation, mosaic complex karyotypes, variable numerical, and structural chromosomal abnormality, along with severe-to-moderate hypo- and hyperdiploidy, and presence of marker chromosomes were the main findings of this study.

Conclusion The result shows that the detection of chromosomal instability was important for preliminary diagnosis, treatment, prognosis, and further management. So the present study provided additional information about chromosomal instability in hematological cancer at Kolkata and adjoining regions.

Chronic Neutrophilic Leukemia with Monocytosis

Chronic neutrophilic leukaemia is a very rare disease with diagnosis based on persistent leucocytosis >25×10³/μl and monocytes <1×10³/μl. The revised WHO criteria 2016 included CSF3R gene mutations as a diagnostic finding. We report the case of a 77-year-old man who was found to have asymptomatic persistent mature neutrophilic leucocytosis with monocytosis. Molecular study confirmed the presence of a CSF3R gene mutation in the absence of morphological or genetic features of myelodysplasia or other forms of myelodysplastic syndrome. The patient's medical history was significant for coronary artery disease, hypertension, chronic obstructive pulmonary disease, bilateral cystic bronchiectasis, moderate pulmonary hypertension, tuberculosis treated 27 years previously, hypothyroidism, and a thyroid nodule. He had hepatosplenomegaly but no lymphadenopathy, and no other malignancy was seen on computed tomography (CT) scanning. At the time of evaluation, he was free of symptoms and had no evidence of infection or drug-induced leucocytosis. The patient was referred to an oncology centre and treated with hydroxyurea and subsequently azacitidine. However, he developed pancytopenia with bone marrow aplasia. He died with neutropenia sepsis. The presence of persistent monocytosis in this case created a diagnostic dilemma as to whether the disease was a variant of chronic neutrophilic leukaemia or was reactive monocytosis.

LEARNING POINTS

The presence of a CSF3R gene mutation is diagnostic for chronic neutrophilic leukaemia (CNL).The monocytosis in this patient might have been a new variant of CNL.

Classification of Monocytes, Promonocytes and Monoblasts Using Deep Neural Network Models: An Area of Unmet Need in Diagnostic Hematopathology

The accurate diagnosis of chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML) subtypes with monocytic differentiation relies on the proper identification and quantitation of blast cells and blast-equivalent cells, including promonocytes. This distinction can be quite challenging given the cytomorphologic and immunophenotypic similarities among the monocytic cell precursors. The aim of this study was to assess the performance of convolutional neural networks (CNN) in separating monocytes from their precursors (i.e., promonocytes and monoblasts). We collected digital images of 935 monocytic cells that were blindly reviewed by five experienced morphologists and assigned into three subtypes: monocyte, promonocyte, and blast. The consensus between reviewers was considered as a ground truth reference label for each cell. In order to assess the performance of CNN models, we divided our data into training (70%), validation (10%), and test (20%) datasets, as well as applied fivefold cross validation. The CNN models did not perform well for predicting three monocytic subtypes, but their performance was significantly improved for two subtypes (monocyte vs. promonocytes + blasts). Our findings (1) support the concept that morphologic distinction between monocytic cells of various differentiation level is difficult; (2) suggest that combining blasts and promonocytes into a single category is desirable for improved accuracy; and (3) show that CNN models can reach accuracy comparable to human reviewers (0.78 ± 0.10 vs. 0.86 ± 0.05). As far as we know, this is the first study to separate monocytes from their precursors using CNN.

RAS mutations drive proliferative chronic myelomonocytic leukemia via a KMT2A-PLK1 axis

Proliferative chronic myelomonocytic leukemia (pCMML), an aggressive CMML subtype, is associated with dismal outcomes. RAS pathway mutations, mainly NRASG12D, define the pCMML phenotype as demonstrated by our exome sequencing, progenitor colony assays and a Vav-Cre-NrasG12D mouse model. Further, these mutations promote CMML transformation to acute myeloid leukemia. Using a multiomics platform and biochemical and molecular studies we show that in pCMML RAS pathway mutations are associated with a unique gene expression profile enriched in mitotic kinases such as polo-like kinase 1 (PLK1). PLK1 transcript levels are shown to be regulated by an unmutated lysine methyl-transferase (KMT2A) resulting in increased promoter monomethylation of lysine 4 of histone 3. Pharmacologic inhibition of PLK1 in RAS mutant patient-derived xenografts, demonstrates the utility of personalized biomarker-driven therapeutics in pCMML.

Clinical and Molecular Approach to Adult-Onset, Neoplastic Monocytosis

PURPOSE OF REVIEW

In this review, we provide a comprehensive and contemporary understanding of malignant monocytosis and provide a framework by which the appropriate diagnosis with malignant monocytosis can be rendered.

RECENT FINDINGS

Increasing data support the use of molecular data to refine the diagnostic approach to persistent monocytosis. The absence of a TET2, SRSF2, or ASXL1 mutation has ≥ 90% negative predictive value for a diagnosis of CMML. These data may also reliably differentiate chronic myelomonocytic leukemia, the malignancy that is most associated with mature monocytosis, from several other diseases that can be associated with typically a lesser degree of monocytosis. These include acute myelomonocytic leukemia, acute myeloid leukemia with monocytic differentiation, myelodysplastic syndromes, and myeloproliferative neoplasms driven by BCR-ABL1, PDGFRA, PDGFRB, or FGFR1 rearrangements or PCM1-JAK2 fusions among other rarer aberrations. The combination of monocyte partitioning with molecular data in patients with persistent monocytosis may increase the predictive power for the ultimate development of CMM but has not been prospectively validated. Many conditions, both benign and malignant, can be associated with an increase in mature circulating monocytes. After reasonably excluding a secondary or reactive monocytosis, there should be a concern for and investigation of malignant monocytosis, which includes hematopathologic review of blood and marrow tissues, flow cytometric analysis, and cytogenetic and molecular studies to arrive at an appropriate diagnosis.

Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding

Purpose of Review

Monocytosis is a frequently encountered clinical condition that needs appropriate investigation due to a broad range of differential diagnoses. This review is meant to summarize the latest literature in the diagnostic testing and interpretation and offer a stepwise diagnostic approach for a patient presenting with monocytosis.

Recent Findings

Basic studies have highlighted the phenotypic and functional heterogeneity in the monocyte compartment. Studies, both translational and clinical, have provided insights into why monocytosis occurs and how to distinguish the different etiologies. Flow cytometry studies have illustrated that monocyte repartitioning can distinguish chronic myelomonocytic leukemia, a prototypical neoplasm with monocytosis from other reactive or neoplastic causes.

Summary

In summary, we provide an algorithmic approach to the diagnosis of a patient presenting with monocytosis and expect this document to serve as a reference guide for clinicians.

Myelomonocytic skewing in chronic myelomonocytic leukemia: phenotypic, molecular and biologic features and impact on survival

BACKGROUND

Myelomonocytic skewing is considered as a key pathophysiologic phenomenon in chronic myelomonocytic leukemia (CMML), but its prevalence and potential correlation with phenotypic, genotypic, and clinical features are poorly defined.

METHODS

Skewed differentiation toward the myelomonocytic over erythroid commitment as indicated by an inverse ratio of myelomonocytic/erythroid colonies was investigated in 146 patients with CMML by semisolid in vitro cultures.

RESULTS

There was a high prevalence of myelomonocytic skewing in patients with CMML (120/146, 82%); whereas, this phenomenon was rare in normal individuals (1/98, 1%). Patients with CMML with myelomonocytic skewing had higher white blood cell and peripheral blast cell counts, and lower platelet values. The number of mutations in genes of the epigenetic and/or splicing category was higher in CMML patients with as compared with patients without skewing. Patients with myelomonocytic skewing had more frequently mutations in RASopathy genes and higher growth factor independent myeloid colony formation. Interestingly, the lack of myelomonocytic skewing discriminated patients with CMML with a particularly favorable prognosis (60 vs 19 months, P = .003) and a minimal risk of transformation.

CONCLUSION

Myelomonocytic skewing as determined by semisolid cultures can discriminate subgroups of patients with CMML with a different phenotype, a different genotype, and a different prognosis.

Occurrence of a Clonal T-Cell Population in a Case of Chronic Myelomonocytic Leukemia

Chronic myelo-monocytic leukemia (CMML) is an aggressive myeloid neoplasm with some features of a myelodysplastic syndrome (MDS) and others of a myeloproliferative neoplasm (MPN). Rarely, patients with CMML have a co-existing lympho-proliferative disorder (LPD). In most cases, the lymphoid neoplasm is diagnosed first, and the CMML is considered to be a secondary therapy-induced form of leukemia. We report herein a unique case of de-novo CMML, with an underlying clonal T-cell population and describe its clinical presentation and laboratory findings. A 70-year old male presented with a 3-month history of cough, dsypnea, abdominal distension, and low-grade fever. Physical and radiological examination revealed hepatosplenomegaly but no lymphadenopathy. Peripheral blood had absolute monocytosis with marrow showing CMML with 10% blasts along with dysplasia in myeloid and erythroid lineages. Flow cytometry indicated possibility of chronic myelo-monocytic leukemia with 13% monocytic cells along with an additional clonal population of gamma/delta T cells (15%) with aberrant immunophenotype. Polymerase chain reaction (PCR) analysis was positive for clonal T-cell rearrangement. A diagnosis of CMML with an underlying clonal T-CLPD was made. The synchronous occurrence of CMML and T-cell neoplasm may be attributed to a genetic mutation common to both. Currently, there are no treatment guidelines for group of patients; hence individualized therapeutic strategies should be implemented to enable symptomatic improvement and provide optimum care.

Real-world data of chronic myelomonocytic leukemia: A chinese single-center retrospective study

Chronic myelomonocytic leukemia (CMML) is a rare disease of elderly people characterized by the presence of sustained peripheral blood monocytosis, overlapping features of myeloproliferation, and myelodysplasia. We present a large retrospective study of 156 CMML patients in China. Mean age at diagnosis was 68 years old (range 23‐91). According to the CMML‐specific prognostic scoring system (CPSS), 10 patients (8.3%) were low risk, 27 patients (22.5%) were intermediate‐1 risk, 72 patients (60%) were intermediate‐2 risk, and 11 patients (9.2%) were high risk. A total of 90 patients (57.7%) received hypomethylating agents (HMAs) treatment, 19 patients (12.2%) received chemotherapy and 47 patients (30.1%) received the best supportive care. Seventeen patients (10.9%) underwent allogeneic hematopoietic stem cell transplantation (allo‐SCT) after HMAs treatment or chemotherapy. With a median follow‐up of 35.3 months, overall response rate (ORR) was 69.5% in the HMAs ± chemotherapy group, 79.5% in the HMAs monotherapy group, 60.0% in the HMAs + chemotherapy group, and 37.5% in the chemotherapy group. HMAs monotherapy group had prolonged OS compared with the chemotherapy group (23.57 months vs. 11.73 months; p = 0.035). Patients who achieved ORR had prolonged OS (25.83 months vs. 8.00 months; p < 0.001) and LFS (20.53 months vs. 6.80 months; p < 0.001) compared with those not achieved ORR in the HMA ± chemotherapy group. By univariate analysis, only higher hemoglobulin (≥80 g/L) and lower serum LDH levels (<300 U/L) predicted for better OS and LFS. By multivariate analysis, only Hb ≥ 80 g/L predicted for prolonged OS, Hb ≥ 80 g/L, and monocytes < 3 × 109/L predicted for prolonged LFS. In summary, our study highlights the benefit of HMAs therapy in CMML, but we still need to develop novel therapeutics to achieve better outcomes.

A rare cause of acute kidney injury with chronic myelomonocytic leukemia

An 80-year-old man with myelodysplastic syndrome developed acute kidney injury (AKI) and peripheral blood monocyte-dominant leukocytosis. Glomerular disease was suspected from urinalysis, which showed proteinuria and microscopic hematuria with red cell casts. Eventually, he died of respiratory failure, after which a postmortem was performed. In the glomeruli, the extracapillary space was filled with numerous mononuclear cells and erythrocytes. At first interpretation, the glomerular findings appeared to represent cellular crescents. However, immunostaining revealed that the extracapillary mononuclear cells were in fact leukemic cells. Furthermore, tubular injury due to marked accumulation of lysozyme was also recognized together with infiltration of leukemic cells in the interstitium. The diagnosis of kidney infiltration by chronic myelomonocytic leukemia (CMML) and lysozyme-induced tubular injury was eventually made. Our case is the first report showing extracapillary infiltration of leukemic cells by immunostaining. In addition, lysozyme-induced tubular injury is a forgotten cause of kidney injury in patients with CMML. This case teaches us the rare and forgotten causes of AKI with CMML.

Spectrum of Kidney Involvement in Patients with Myelodysplastic Syndromes

Introduction

Myelodysplastic syndromes (MDS) are characterized by a high prevalence of associated autoimmune manifestations. Kidney involvement has been rarely reported in MDS patients. We report on the spectrum of kidney pathological findings in MDS patients.

Methods

We retrospectively identified MDS patients who had undergone a kidney biopsy between 2001 and 2019 in nine Swiss and French nephrology centres.

Results

Nineteen patients (median age 74 years [63-83]) were included. At the time of kidney biopsy, eleven (58%) patients had extra-renal auto-immune manifestations and sixteen (84%) presented with acute kidney injury. Median serum creatinine at diagnosis was 2.8 mg/dL [0.6-8.3] and median urinary protein to creatinine ratio was 1.2 g/g [0.2-11]. Acute tubulo-interstitial nephritis (TIN) was present in seven (37%) patients. Immunofluorescence study in one patient with acute TIN disclosed intense IgG deposits along the tubular basement membrane and Bowman’s capsule. Other kidney pathological features included ANCA-negative pauci-immune necrotizing and crescentic glomerulonephritis (n = 3), membranous nephropathy (n = 2), IgA nephropathy (n = 1), IgA vasculitis (n = 1), immunoglobulin-associated membrano-proliferative glomerulonephritis type I (n=1), crescentic C3 glomerulopathy (n = 1), fibrillary glomerulonephritis (n = 1) and minimal change disease (n = 1). Eleven (58%) patients received immunosuppressive treatments, among whom one developed a severe infectious complication. After a median follow-up of 7 month [1-96], nine (47%) patients had chronic kidney disease stage 3 (n = 6) or 4 (n = 3) and five (26%) progressed to end-stage kidney disease. Three patients died.

Conclusions

MDS are associated to several autoimmune kidney manifestations, predominantly acute TIN. MDS are to be listed among the potential causes of autoimmune TIN.

Leukemic retinopathy, the first expression in a case of chronic myelomonocytic leukemia - a case report

A 68-year-old male addressed to our clinic complaining of gradual loss of visual acuity and perceptual distortions. He had a history of extrathoracic hematoma and essential hypertension. The clinical assessment revealed bilateral retinal hemorrhages and white-green foveal and extrafoveal areas. The complete blood count (CBC) suggested a hematologic disorder.

Myeloid Disease with the CSF3R T618I Mutation after CLL

Chronic lymphocytic leukemia (CLL) is frequently an indolent diagnosis, with most of the patients being under surveillance for long time. There is an increased risk of a second neoplasia in CLL, rarely hematological (in the myeloid lineage is even rarer). A 58-year-old male was diagnosed with CLL in 2012, remaining in regular surveillance until 2014. Then, the CLL progressed, and 6 cycles of rituximab, fludarabine, and cyclophosphamide were prescribed with partial response. He remained in surveillance and suffered 2 episodes of autoimmune hemolytic anemia until 2019. Then, the hemolytic anemia relapsed and a neutrophilia became evident (progressing slowly), as well as a thrombocytopenia and splenomegaly without adenopathy were found. The bone marrow aspirate showed a chronic myeloproliferative disease without dysplasia. A peripheral blood search for the CSF3R mutation (T618I) was positive, also suggesting Chronic Neutrophilic Leukemia (CNL). For a discrete monocytosis, a chronic myelomonocytic leukemia (CMML) was also considered. Hydroxyurea was then prescribed. The T618I CSF3R mutation is highly suggestive of CNL (being diagnostic criteria for CNL); however, this case may also suggest CMML as a possible diagnosis (there are other mutations in the CSF3R gene described for CMML, but not the T618I, which is highly exclusive of CNL according to the literature). To our knowledge, this is the first report of a possible CNL in a CLL patient (the opposite was already described in 1998).

Successful long-term treatment with azacitidine in patient with chronic myelomonocytic leukemia

The purpose of this article was to present a case of successful long term treatment with azacitidine in patient with Chronic Myelomonocytic Leukemia (CMML) and discussing possible contributing factors for its long term efficacy. Data from our case were compared with similar data available in the literature. Effective treatment with azacitidine resulted in overall survival of 11 years 5 months and we showed that applying multiple cycles of treatment is feasible. Our patient received 71 cycles of treatment with total duration of 7 years and 3 months. Our report about a patient with CMML and a good clinical course revealed, that long term treatment with azacitidine is feasible in some patients. Initially low bone marrow blast count, a relatively small malignant CMML clone, reduction of spleen size and fast platelet response seemed to be factors determining long term response to treatment in our patient. More data on CMML treatment by Hypomethylating Agents and their analysis are needed in order to make firm conclusions.

NPM1-Mutated Myeloid Neoplasms with <20% Blasts: A Really Distinct Clinico-Pathologic Entity?

Nucleophosmin (NPM1) gene mutations rarely occur in non-acute myeloid neoplasms (MNs) with <20% blasts. Among nearly 10,000 patients investigated so far, molecular analyses documented NPM1 mutations in around 2% of myelodysplastic syndrome (MDS) cases, mainly belonging to MDS with excess of blasts, and 3% of myelodysplastic/myeloproliferative neoplasm (MDS/MPN) cases, prevalently classified as chronic myelomonocytic leukemia. These uncommon malignancies are associated with an aggressive clinical course, relatively rapid progression to overt acute myeloid leukemia (AML) and poor survival outcomes, raising controversies on their classification as distinct clinico-pathologic entities. Furthermore, fit patients with NPM1-mutated MNs with <20% blasts could benefit most from upfront intensive chemotherapy for AML rather than from moderate intensity MDS-directed therapies, although no firm conclusion can currently be drawn on best therapeutic approaches, due to the limited available data, obtained from small and mainly retrospective series. Caution is also suggested in definitely diagnosing NPM1-mutated MNs with blast count <20%, since NPM1-mutated AML cases frequently present dysplastic features and multilineage bone marrow cells showing abnormal cytoplasmic NPM1 protein delocalization by immunohistochemical staining, therefore belonging to NPM1-mutated clone regardless of blast morphology. Further prospective studies are warranted to definitely assess whether NPM1 mutations may become sufficient to diagnose AML, irrespective of blast percentage.