Chronic myelomonocytic leukemia: Forefront of the field in 2015

Kidney Involvement in Patients With Chronic Myelomonocytic Leukemia or BCR-ABL-Negative Myeloproliferative Neoplasms

Introduction

The identification of specific molecular signatures and the development of new targeted drugs have changed the paradigm of onco-nephrology, now allowing a multiscale approach of kidney involvement related to hematologic malignancies relying on combined hematologic and molecular assessments. In this study, we aimed to refine the spectrum of kidney disorders associated with chronic myelomonocytic leukemia (CMML) or BCR-ABL–negative myeloproliferative neoplasms (MPNs), 2 very rare conditions scarcely described.

Methods

Case series. Patients with myeloid neoplasms who were referred to Toulouse University Hospital Nephrology Unit and were diagnosed with acute kidney injury (AKI), chronic kidney disease (CKD), or urine abnormalities were retrospectively included.

Results

Eighteen patients (males n=13, CMML n=8, essential thrombocytosis [ET] n=7, polycythemia vera [PV] n=1, and myelofibrosis n=2) developed kidney disease 7.7±2 years after the diagnosis of the malignancy. Twelve patients had AKI at presentation. Eight patients had glomerular presentation (high-range proteinuria 33%, microscopic hematuria 56%). Kidney biopsy (n=14) showed various patterns, including pauci-immune glomerulosclerosis (n=5), extramedullary hematopoiesis (n=6), or tubular atrophy and interstitial fibrosis with polymorphic inflammation (n=8). Immunostaining of CD61 confirmed the infiltration of megakaryocytes within glomeruli or interstitium in 5 of 8 patients. Other pictures of glomerulopathy were identified in 3 patients (IgA nephropathy n=2, AA amyloidosis n=1). Massive kidney infiltration by CMML was identified in 1 patient. After a mean follow-up of 24±6 months, malignancy was considered as stable in 11 patients (61%), but 22% of patients had progressed to end-stage renal failure. The remaining had persistently reduced kidney function. No correlation between the malignancy and the renal presentation and outcomes could be identified.

Conclusions

Kidney complications of CMML/MPN are heterogenous, and kidney biopsy may help to identify new molecular targets to prevent the development of kidney fibrosis.

Chronic Myelomonocytic Leukemia Presenting With Polyserositis and Seropositivity for Rheumatoid Arthritis

Chronic myelomonocytic leukemia (CMML) is a rare clonal stem cell disorder associated with clinical and pathologic of myelodysplasia and myeloproliferation. Systemic autoimmune/inflammatory disorders (SAID) and polyserositis have been associated with CMML. These manifestations can be observed concomitantly, shortly before diagnosis or anytime along the course of illness. We report a case of myeloproliferative CMML who presented with polyserositis and positive serology for rheumatoid arthritis. Retrospective studies of myelodysplasia/CMML have reported 15% to 25% incidence of SAID. The most commonly observed disorders include systemic vasculitis, connective tissue diseases, polychondritis, seronegative arthritis, and immune thrombocytopenia. SAID does not confer adverse prognosis in retrospective studies. Polyserositis is less common; this may result from leukemic infiltrate or result from autoimmunity. Treatment of serositis includes steroids and cytoreductive agents. Serositis may confer poor prognosis and hypomethylating therapy may improve the outcome.

Proposed diagnostic criteria for classical chronic myelomonocytic leukemia (CMML), CMML variants and pre-CMML conditions

Chronic myelomonocytic leukemia (CMML) is a myeloid neoplasm characterized by dysplasia, abnormal production and accumulation of monocytic cells and an elevated risk of transforming into acute leukemia. Over the past two decades, our knowledge about the pathogenesis and molecular mechanisms in CMML has increased substantially. In parallel, better diagnostic criteria and therapeutic strategies have been developed. However, many questions remain regarding prognostication and optimal therapy. In addition, there is a need to define potential pre-phases of CMML and special CMML variants, and to separate these entities from each other and from conditions mimicking CMML. To address these unmet needs, an international consensus group met in a Working Conference in August 2018 and discussed open questions and issues around CMML, its variants, and pre-CMML conditions. The outcomes of this meeting are summarized herein and include diag nostic criteria and a proposed classification of pre-CMML conditions as well as refined minimal diagnostic criteria for classical CMML and special CMML variants, including oligomonocytic CMML and CMML associated with systemic mastocytosis. Moreover, we propose diagnostic standards and tools to distinguish between 'normal', pre-CMML and CMML entities. These criteria and standards should facilitate diagnostic and prognostic evaluations in daily practice and clinical studies in applied hematology.

Alteration in the Cytokine Secretion of Bone Marrow Stromal Cells from Patients with Chronic Myelomonocytic Leukemia Contribute to Impaired Hematopoietic Supportive Activity

Bone marrow stromal cells (BMSCs) represent an important cellular component of the bone marrow microenvironment, which play an important role in supporting and regulating the proliferation and differentiation of hematopoietic stem/progenitor cells (HSPCs). We have previously reported that the ability of BMSCs derived from CMML patients (CMML-BMSCs) in supporting the expansion of cord blood (CB) CD34⁺ cells was significantly reduced compared to BMSCs derived from healthy donors (HD-BMSCs). In addition, CMML-BMSCs led to a skewed differentiation of CB CD34⁺ cells favoring myeloid lineage compared with HD-BMSCs. To assess whether the altered cytokine secretion was one of the mechanisms to mediate the impaired hematopoietic supportive activity of CMML-BMSCs, a transwell coculture followed by cytokine array was performed. We showed that noncontacted coculture with CMML-BMSCs preferentially promoted the differentiation of CB CD34⁺ cells toward myeloid lineage. The expression levels of multiple cytokines (IL-6, IL-8, and GRO-β) were markedly reduced in CMML-BMSCs compared with HD-BMSCs. By supplementing IL-6, IL-8, or GRO-β, the hematopoietic supportive activity of CMML-BMSCs was partially restored. These results suggested that BMSCs may contribute to the pathogenesis of CMML by altering their cytokine secretion, which will shed light on the further investigation to develop novel therapeutic strategies for CMML patients.

Outcome of patient with high-risk chronic myelomonocytic leukemia, treated with decitabine prior to transformation to acute myeloid leukemia: A case report

The present study describes a patient with high-risk chronic myelomonocytic leukemia (CMML), for whom decitabine therapy achieved partial remission, prior to a sudden transformation to acute myeloid leukemia (AML) and an inferior outcome. The 53-year-old male reported easily bruising for 5 months. Examination indicated a diagnosis of CMML. Chromosome analysis identified a 48, XY, +8, +21 karyotype, classifying the patient as high-risk, according to a clinical/molecular CPSS (CPSS-Mol) model. Gene sequencing detected a mutation in DNA methyltransferase 3α, which is relatively rarely identified in CMML and has recently been reported to have an independent prognostic impact on overall survival time. Partial remission was achieved with decitabine treatment, and hematologic improvement was observed subsequent to 2 cycles of treatment. However, a sudden transformation to AML led to fatality of the patient. This case suggests that decitabine may be an effective therapeutic for high-risk CMML; however, the response may be temporary, and the ultimate outcome may be extremely poor. Therefore, novel treatment strategies of CMML, including combination therapies with decitabine, or targeted drugs, including Janus kinase inhibitors or granulocyte-macrophage colony stimulating factor monoclonal antibodies, require investigation.

Systematic Literature Review of Treatment Options and Clinical Outcomes for Patients With Higher-Risk Myelodysplastic Syndromes and Chronic Myelomonocytic Leukemia

High-dose chemotherapy with allogeneic hematopoietic stem cell transplantation (allo-HSCT) can produce long-term remission in patients with higher-risk myelodysplastic syndromes (HR-MDS) and chronic myelomonocytic leukemia (CMML). However, this treatment regimen is not appropriate for elderly and/or comorbid patients; in these cases, azacitidine is a standard treatment. This systematic review was conducted to evaluate real-world evidence of treatment options for patients with HR-MDS/CMML. Medline and Embase (January 2006 to May 2016) were searched, in addition to conference proceedings and treatment guideline reviews. Studies on clinical effectiveness/efficacy outcomes with a sample size ≥50 patients were included. From 1061 unique citations identified, 87 full-text articles were reviewed, of which 24 articles reported at least 1 outcome of interest. Studies showed that HR-MDS/CMML patients treated with a conventional chemotherapy regimen (CCR) have poorer overall survival (OS). Key findings from individual HR-MDS studies showed improved survival with azacitidine over CCRs and higher overall response rates with clofarabine relative to low-dose cytosine arabinoside (but no significant difference in 2-year OS favoring clofarabine). OS was highest for patients treated with allo-HSCT. Findings indicate limited real-world data on treatment strategies available for HR-MDS/CMML patients. Most studies address the effect of chemotherapy or allo-HSCT on clinical outcomes, so are not applicable to elderly/comorbid patients who are too frail for those treatments. In particular, our analysis revealed limited evidence on viable options after failure of treatment with azacitidine, identifying a significant unmet need in this patient population.

Blastic Transformation in Mexican Population With Chronic Myelomonocytic Leukemia

BACKGROUND

Chronic myelomonocytic leukemia (CMML) is the most aggressive of chronic leukemias, with short overall survival and a high transformation rate to acute leukemia. We investigated the factors related to blastic transformation in a Mexican population treated at a tertiary referral center.

PATIENTS AND METHODS

The records of patients with a diagnosis of CMML from 2000 to 2015 were reviewed. A total of 54 patients were included, with a median age of 71 years and an overall survival of 16 months. The patients with incomplete data were excluded. IBM SPSS Statistics, version 21.0, software was used to perform the statistical analysis.

RESULTS

The rate of blastic transformation was 33% (18 patients), and the interval time to progression was 9 months (range, 0-87 months). Comparing the patients who did not undergo blastic transformation to those who did, those with progression to acute leukemia tended to be younger (age, 58 vs. 71 years; P = .001), to have a greater peripheral blood blast count (≥ 2% vs. 0%; P = .003), and were more likely to have immature myeloid precursors circulating in the peripheral blood (94% vs. 64%; P = .02). On multivariate analysis, younger age continued to be a statistically significant factor for progression (hazard ratio, 0.97; 95% confidence interval, 0.929-0.987).

CONCLUSION

Mexican patients with CMML that progressed to overt acute leukemia were considerably younger, with a higher tumor burden and short overall survival. In this population, it is important to consider more aggressive treatment at diagnosis, focusing on high-dose chemotherapy and hematopoietic stem cell transplantation within a short period.

Involvement of mitochondrial dynamics in the antineoplastic activity of cisplatin in murine leukemia L1210 cells

Leukemia is a type of hematopoietic stem cell malignant cloned disease with high mortality. Cisplatin-based chemotherapy is one of the most common treatments for leukemia. Similar to other chemotherapeutic agents, cisplatin resistance has become a serious issue in cancer therapy. In the present study, we investigated the role of mitochondrial dynamics in the antineoplastic activity of cisplatin in murine leukemia L1210 cells. Firstly, the L1210 cell line resistant to cisplatin (L1210/DDP) was established. Compared to its parental cell line, the IC50 value of cisplatin in the L1210/DDP cells was increased 10-fold. Mitofusins (Mfn1 and Mfn2), mitochondrial outer membrane fusion proteins, were markedly upregulated in the L1210/DDP cells, whereas the expression of fission protein Drp1 and inner membrane fusion protein OPA1 were not significantly altered. In addition, mitofusins were also upregulated in the parental L1210 cells subjected to cisplatin stress. To investigate the role of mitochondrial dynamics in the antineoplastic activity of cisplatin, the effect of mitochondrial division inhibitor (Mdivi)-1 on cisplatin‑induced cell death, caspase-3 cleavage and ROS production was examined in L1210 cells. We found that 5 µM of Mdivi-1 efficiently attenuated cisplatin-induced cell death, caspase activation and intracellular ROS increase in L1210 cells. Our data indicated that mitochondrial dynamics play an important role in the antineoplastic activity of cisplatin, and mitofusin-mediated mitochondrial fusion may be involved in the process of cisplatin resistance in leukemia cells. Therefore, the present study revealed that mitochondrial dynamics may be a potential target used to improve the antineoplastic activity of cisplatin in leukemia in the future.

Few-Layer Graphene Kills Selectively Tumor Cells from Myelomonocytic Leukemia Patients

In the cure of cancer, a major cause of today's mortality, chemotherapy is the most common treatment, though serious frequent challenges are encountered by current anticancer drugs. We discovered that few-layer graphene (FLG) dispersions have a specific killer action on monocytes, showing neither toxic nor activation effects on other immune cells. We confirmed the therapeutic application of graphene on an aggressive type of cancer that is myelomonocytic leukemia, where the monocytes are in their malignant form. We demonstrated that graphene has the unique ability to target and boost specifically the necrosis of monocytic cancer cells. Moreover, the comparison between FLG and a common chemotherapeutic drug, etoposide, confirmed the higher specificity and toxicity of FLG. Since current chemotherapy treatments of leukemia still cause serious problems, these findings open the way to new and safer therapeutic approaches.

Routine blood examinations combined with morphological analysis for the diagnosis of myelodysplastic/myeloproliferative neoplasms

In 2008, the World Health Organization (WHO) introduced a new hematological neoplasm category; myelodysplastic/myeloproliferative neoplasms (MDS/MPN), which included four main subcategories. This disease is often misdiagnosed, which delays effective therapy. The present study evaluated the role of routine blood examinations and morphological analysis of peripheral blood cells in the reliable diagnosis of MDS/MPN. In total, 236 adult MDS/MPN patients were analyzed. The analysis included 10 routine blood parameters measured using a Sysmex XE-2100™, 3 differential percentage parameters and 7 morphological features of peripheral blood cells which were analyzed by optical microscopy, and 3 differential absolute count numbers obtained based on the corresponding differential percentages and absolute count of blood cells. The parameters were compared among the subcategories and a value of P<0.05 was considered to indicate a statistically significant difference. The median white blood cell and hemoglobin counts of the patients were 18.0×10⁹/l and 88 g/l, respectively. The proportion of monocytes increased to 8% (1.82×10⁹/l), the proportion of blast cells increased to 1% (0.5×10⁹/l) and that of neutrophil precursors increased to 10% (1.98×10⁹/l). A total of 87% of all patients presented with hypogranulation and 71% presented with abnormal condensed nuclear chromatin in granulocytes. Atypical monocytes were observed in 73% of all patients and Pseudo-Pelger cells were observed in 60%. Significant differences were detected among the subcategories. The present study demonstrated that combining blood routine parameters and the morphological analysis of peripheral blood cells have an essential role in the reliable diagnosis of MDS/MPN based on WHO categories.

Chronic myelomonocytic leukemia mimicking hematologic systemic lupus erythematosus

The relationship between primary hematologic disease and rheumatologic manifestations is well known, especially acute lymphocytic leukemia, lymphomas, plasma cell dyscrasias and myelodysplastic syndrome (MDS). Currently, more has been described about autoimmune manifestations in chronic myelomonocytic leukemia (CMML). Many different clinical scenarios may lead a patient with MDS/CMML initially to seek a rheumatological unit. Autoimmune features such as polymyalgia rheumatic symptoms, myositis, neutrophilic dermatosis, cutaneous vasculitis and positive antinuclear antibodies (ANA) are some examples of clinical presentation of MDS/CMML. Moreover, peripheral cytopenias are a common initial presentation both for systemic lupus erythematous (SLE) and MDS/CMML. The aim of this study was to describe a case of an elderly woman with thrombocytopenia and positivity of antibodies to anti-extractable nuclear antigens (anti-ENA) as initial manifestation of CMML mimicking SLE, and to present some clues that encourage the clinician to perform a bone marrow study in such a clinical scenario.

Transformation of Canine Lymphoma/Leukemia to More Aggressive Diseases: Anecdotes or Reality?

Transformation is the evolution of an indolent lymphoma/leukemia to an aggressive lymphoma, typically harboring a very poor prognosis. This phenomenon is well described in humans, but underestimated in dogs although recognized as a possible evolution of indolent lymphomas/leukemias. In canine chronic leukemias, blast crisis (mainly in myeloid) and Richter syndrome (transformation into a high grade lymphoma) (mainly in B-cell lymphocytic leukemia) have been reported. Transformation is a possible event also in canine low grade lymphomas, although rare. The increased knowledge has also generated new questions and posed challenges that need to be addressed to improve outcome, including the recognition of the clinical characteristics at diagnosis associated with a higher risk of transformation in an attempt of anticipating the typical evolution.