Myeloid malignancies with translocation t(4;12)(q11-13;p13): molecular landscape, clonal hierarchy and clinical outcomes.

Translocation t(4;12)(q11-13;p13) is a recurrent but very rare chromosomal aberration in acute myeloid leukaemia (AML) resulting in the non-constant expression of a CHIC2/ETV6 fusion transcript. We report clinico-biological features, molecular characteristics and outcomes of 21 cases of t(4;12) including 19 AML and two myelodysplastic syndromes (MDS). Median age at the time of t(4;12) was 78 years (range, 56-88). Multilineage dysplasia was described in 10 of 19 (53%) AML cases and CD7 and/or CD56 expression in 90%. FISH analyses identified ETV6 and CHIC2 region rearrangements in respectively 18 of 18 and 15 of 17 studied cases. The t(4;12) was the sole cytogenetic abnormality in 48% of cases. The most frequent associated mutated genes were ASXL1 (n = 8/16, 50%), IDH1/2 (n = 7/16, 44%), SRSF2 (n = 5/16, 31%) and RUNX1 (n = 4/16, 25%). Interestingly, concurrent FISH and molecular analyses showed that t(4;12) can be, but not always, a founding oncogenic event. Median OS was 7.8 months for the entire cohort. In the 16 of 21 patients (76%) who received antitumoral treatment, overall response and first complete remission rates were 37% and 31%, respectively. Median progression-free survival in responders was 13.7 months. Finally, t(4;12) cases harboured many characteristics of AML with myelodysplasia-related changes (multilineage dysplasia, MDS-related cytogenetic abnormalities, frequent ASXL1 mutations) and a poor prognosis.

CANOMAD: a neurological monoclonal gammopathy of clinical significance that benefits from B-cell-targeted therapies.

CANOMAD (chronic ataxic neuropathy, ophthalmoplegia, immunoglobulin M [IgM] paraprotein, cold agglutinins, and disialosyl antibodies) is a rare syndrome characterized by chronic neuropathy with sensory ataxia, ocular, and/or bulbar motor weakness in the presence of a monoclonal IgM reacting against gangliosides containing disialosyl epitopes. Data regarding associated hematologic malignancies and effective therapies in CANOMAD are scarce. We conducted a French multicenter retrospective study that included 45 patients with serum IgM antibodies reacting against disialosyl epitopes in the context of evocating neurologic symptoms. The main clinical features were sensitive symptoms (ataxia, paresthesia, hypoesthesia; n = 45, 100%), motor weakness (n = 18, 40%), ophthalmoplegia (n = 20, 45%), and bulbar symptoms (n = 6, 13%). Forty-five percent of the cohort had moderate to severe disability (modified Rankin score, 3-5). Cold agglutinins were identified in 15 (34%) patients. Electrophysiologic studies showed a demyelinating or axonal pattern in, respectively, 60% and 27% of cases. All patients had serum monoclonal IgM gammopathy (median, 2.6 g/L; range, 0.1-40 g/L). Overt hematologic malignancies were diagnosed in 16 patients (36%), with the most frequent being Waldenström macroglobulinemia (n = 9, 20%). Forty-one patients (91%) required treatment of CANOMAD. Intravenous immunoglobulins (IVIg) and rituximab-based regimens were the most effective therapies with, respectively, 53% and 52% of partial or better clinical responses. Corticosteroids and immunosuppressive drugs were largely ineffective. Although more studies are warranted to better define the optimal therapeutic sequence, IVIg should be proposed as the standard of care for first-line treatment and rituximab-based regimens for second-line treatment. These compiled data argue for CANOMAD to be included in neurologic monoclonal gammopathy of clinical significance.

How Recent Advances in Biology of Waldenström's Macroglobulinemia May Affect Therapy Strategy.

PURPOSE OF REVIEW: Waldenström macroglobulinemia (WM) is a rare lymphoproliferative disorder. Up to now, therapeutic choice was not influenced by the biological characteristics of the disease. Here, we will review how recent advances in biology in WM may affect therapy strategy. RECENT FINDINGS: Recently, WM has been described as a new oncogenic model. MyD88 mutation has been described as a key driver mutation and has functional consequences which could be targeted. Other mutations, such as CXCR4 or TP53, have been reported. These mutations are associated with different clinical presentation, prognosis, and treatment response. Mutational status may influence therapeutic choice in some patients but additional data are required. New targeted therapies are on development.

Aplastic anemia in the elderly: a nationwide survey on behalf of the French Reference Center for Aplastic Anemia.

Aplastic anemia is a rare but potentially life-threatening disease that may affect older patients. Data regarding the treatment of aplastic anemia in this ageing population remains scarce. We conducted a retrospective nationwide multicenter study in France to examine current treatments for aplastic anemia patients over 60 years old. Our aims were to evaluate efficacy and tolerance, and to analyze predictive factors for response and survival. Over the course of a decade, 88 patients (median age 68.5 years) were identified in 19 centers, with a median follow up of 2.7 years; 21% had very severe and 36% severe aplastic anemia. We analyzed 184 treatment lines, mostly involving the standard combination of anti-thymocyte globulin and cyclosporine-A (33%), which was also the most frequent first-line treatment (50%). After first-line therapy, 32% of patients achieved a complete response, and 15% a partial response. Responses were significantly better in first line and in patients with good performance status, as well as in those that had followed an anti-thymocyte globulin and cyclosporine-A regimen (overall response rate of 70% after first-line treatment). All treatments were well tolerated by patients, including over the age of 70. Three-year survival was 74.7% (median 7.36 years). Age, Charlson comorbidity index and very severe aplastic anemia were independently associated with mortality. Age, per se, is not a limiting factor to aplastic anemia treatment with anti-thymocyte globulin and cyclosporine-A; this regimen should be used as a first-line treatment in elderly patients if they have a good performance status and low comorbidity index score.

Imaging spectrum of Bing-Neel syndrome: how can a radiologist recognise this rare neurological complication of Waldenström's macroglobulinemia?

OBJECTIVES: Bing-Neel syndrome (BNS) is a rare neurological complication of Waldenström's macroglobulinemia. The aim of this study is to describe the spectrum of radiological manifestations of this syndrome and their prevalence in order to facilitate its early diagnosis. METHODS: Twenty-four patients with BNS were diagnosed between 1994 and 2016 in eight centres in France. We retrospectively examined the medical records of these patients as well as the corresponding literature, focusing on imaging studies. Recorded data were statistically analysed and radiological findings described. RESULTS: The mean age of our patients was 62.4 years (35-80 years). The vast majority of patients were men, with a male to female ratio of 9:1. Findings included parenchymal or meningeal involvement or both. The most common finding was leptomeningeal infiltration, either intracranial or spinal, with a prevalence reaching 70.8%. Dural involvement was present in 37.5% of patients. In 41.7% (10/24) of patients, there was parenchymal involvement with a higher prevalence of brain comparing to medullar involvement (33.3% and 23.1% respectively). High T2 signal of the parenchyma was identified in 41.7% of patients and high signal in diffusion was evident in 25% of them. Intraorbital or periorbital involvement was also detected in four cases. A proposition regarding the appropriate imaging protocol completed our study. CONCLUSION: BNS's diagnosis remains challenging. Central nervous system MRI findings in the setting of known or suspected Waldenström's macroglobulinemia appear to be highly suggestive of BNS and appropriate imaging protocols should be implemented for their depiction. KEY POINTS: • Diagnosis of Bing-Neel syndrome (BNS) remains challenging and recent expert recommendations include MRI in the diagnostic criteria for the syndrome. • The most common radiological manifestations of BNS are leptomeningeal/dural infiltration or parenchymal involvement of brain or spinal cord, but many atypical forms may exist with various presentations. • Appropriate imaging protocol for BNS should include enhanced MRI studies of both brain and spine.

How we manage patients with Waldenström macroglobulinaemia.

Waldenström macroglobulinaemia (WM) is a rare, indolent B-cell lymphoproliferative disorder characterized by cellular involvement in bone marrow and monoclonal IgM production. Symptoms can be related to cytopenias, tumoural involvement, or IgM-related disorders. Somatic mutations in the MYD88 gene have been described in the majority of WM cases. The mutation is responsible for a gain-of-function and induces activation of nuclear factor-κB, for DNA transcription and cell survival. It seems that MYD88 mutation is associated with better prognosis and better response to some treatment. Treatments are started when WM is symptomatic, following systematic biological and morphological assessments. Therapeutic choice depends on age, frailty and urgent efficacy need. In first line, the majority of patients are treated with monoclonal anti-CD20 antibody-based regimens combined with cytotoxic chemotherapy. Rituximab, cyclophosphamide and dexamethasone remain the most commonly used regimen with good safety. Nevertheless, increasing numbers of new drugs are becoming available or are in development. Proteasome inhibitors, such as bortezomib or carfilzmib, showed good and rapid responses. Bruton tyrosine kinase (BTK) inhibitor demonstrated excellent results and is now available for relapse/refractory disease or as first line for some patients. This review highlights the diagnostic procedures and therapeutic approaches in WM.

[Waldenström macroglobulinaemia]. / Maladie de Waldenström.

Waldenström macroglobulinaemia. Waldenström macroglobulinaemia (WM) is a rare, indolent B-cell lymphoproliferative disorder characterized by cellular involvement in bone marrow and monoclonal IgM production. Symptoms can be related to cytopenias, tumoural involvement, or IgM-related disorders. Somatic mutations in the MYD88 gene have been described in the majority of WM cases. Treatments are started when WM is symptomatic, following systematic biological and morphological assessments. Therapeutic choice depends on age, frailty and urgent efficacy need. In first line, the majority of patients are treated with monoclonal anti- CD20 antibody-based regimens combined with cytotoxic chemotherapy. Rituximab, cyclophosphamide and dexamethasone remain the most commonly used regimen with good safety. Nevertheless, increasing numbers of new drugs are becoming available or are in development. Bruton tyrosine kinase (BTK) inhibitor demonstrated excellent results and is now available for relapse/ refractory disease or as first line for some patients.

Maladie de waldenström. La maladie de Waldenström est un syndrome lymphoprolifératif B rare et indolent, représentant 1 à 2 % des hémopathies. Le spectre de ses complications est large ; elles sont liées à l'infiltration tumorale et aux caractéristiques physico-chimiques ou auto-immunes de l'IgM monoclonale. Une mutation somatique sur le gène MYD88 a été décrite dans la majorité des cas de maladie de Waldenström. Un traitement est nécessaire lorsque la maladie est symptomatique. Le choix thérapeutique dépend de l'âge du patient, des comorbidités et de la nécessité d'obtenir une réponse rapide. En première ligne, la majorité des patients sont traités avec une combinaison d'immunochimiothérapie de type rituximab-cyclophosphamide- dexaméthasone. Néanmoins, de nombreux nouveaux médicaments sont disponibles ou en développement. L'ibrutinib, inhibiteur de tyrosine kinase de Bruton, fait partie de l'arsenal thérapeutique avec une bonne efficacité thérapeutique dans la maladie de Waldenström, en première ligne et en rechute.

An unusual case of acute leukemia.

We report the case of a 31 year-old man diagnosed with an atypical acute leukemia difficult to characterize cytologically. The immunophenotyping identified a blastic population co-expressing myeloid, lymphoid B and lymphoid T markers suggesting the diagnosis of either a mixed phenotype acute leukemia (MPAL) or an early T-cell precursor acute lymphoblastic leukemia (ETP-ALL). Because of the poor prognosis linked to these leukemias, the patient benefited from chemotherapy targeting both myeloid and lymphoid components, followed by allogeneic hematopoietic stem cell transplantation. DNA-based techniques analyzing B and T-cell clonality identified partial rearrangements in immunoglobulin and TCR genes, allowing the monitoring of minimal residual disease. This observation highlights the difficulty to classify some atypical cases of acute leukemias. It emphasizes on the complementarity of cytomorphology, immunophenotyping by flow cytometry and molecular techniques in order to promptly characterize and treat these leukemias.

Guideline for the diagnosis, treatment and response criteria for Bing-Neel syndrome.

Bing Neel syndrome is a rare disease manifestation of Waldenström's macroglobulinemia that results from infiltration of the central nervous system by malignant lymphoplasmacytic cells. In this guideline we describe the clinical symptoms, as well as the appropriate laboratory and radiological studies, that can aid in the diagnosis. The presentation of Bing Neel syndrome may be very diverse, and includes headaches, cognitive deficits, paresis, and psychiatric symptoms. The syndrome can present in patients with known Waldenström's macroglobulinemia, even in the absence of systemic progression, but also in previously undiagnosed patients. Diagnostic work-up should include cerebral spinal fluid analysis with multiparameter flow cytometry to establish B-cell clonality, protein electrophoresis and immunofixation for the detection and classification of a monoclonal protein as well as molecular diagnostic testing for immunoglobulin gene rearrangement and mutated MYD88. MRI of the brain and spinal cord is also essential. The second challenge is to expand our knowledge of prognosis and treatment outcome. Prospective clinical trials on Bing Neel syndrome patients that employ uniform treatment along with appropriate laboratory cerebral spinal fluid assessments and standardized MRI protocols will be invaluable, constituting a significant step forward in delineating treatment outcome for this intriguing disease manifestation.

Bing-Neel syndrome, a rare complication of Waldenström macroglobulinemia: analysis of 44 cases and review of the literature. A study on behalf of the French Innovative Leukemia Organization (FILO).

Central nervous system involvement by malignant cells is a rare complication of Waldenström macroglobulinemia, and this clinicopathological entity is referred to as the Bing-Neel syndrome. There is currently no consensus on the diagnostic criteria, therapeutic approaches and response evaluation for this syndrome. In this series, we retrospectively analyzed 44 French patients with Bing-Neel syndrome. Bing-Neel syndrome was the first manifestation of Waldenström macroglobulinemia in 36% of patients. When Waldenström macroglobulinemia was diagnosed prior to Bing-Neel syndrome, the median time interval between this diagnosis and the onset of Bing-Neel syndrome was 8.9 years. This study highlights the possibility of the occurrence of Bing-Neel syndrome without any other evidence of progression of Waldenström macroglobulinemia. The clinical presentation was heterogeneous without any specific signs or symptoms. Biologically, the median lymphocyte count in the cerebrospinal fluid was 31/mm(3). Magnetic resonance imaging revealed abnormalities in 78% of the cases. The overall response rate after first-line treatment was 70%, and the overall survival rate after the diagnosis of Bing-Neel syndrome was 71% at 5 years. Altogether, these results suggest that Bing-Neel syndrome should be considered in the context of any unexplained neurological symptoms associated with Waldenström macroglobulinemia. The diagnostic approach should be based on cerebrospinal fluid analysis and magnetic resonance imaging of the brain and spinal axis. It still remains difficult to establish treatment recommendations or prognostic factors in the absence of large-scale, prospective, observational studies.

Use of Eculizumab in Patients With Allogeneic Stem Cell Transplant-Associated Thrombotic Microangiopathy: A Study From the SFGM-TC.

BACKGROUND: Thrombotic microangiopathy (TMA) occurring after allogeneic hematopoietic stem cell transplantation (HSCT) has a devastating prognosis. Response rates to current therapies (mainly plasma exchange) are unsatisfactory. Thrombotic microangiopathy after allogeneic HSCT shares similarities with atypical hemolytic uremic syndrome (aHUS) in the underlying pathomechanisms. Eculizumab has been associated with impressive results in aHUS. MATERIALS AND METHODS: We retrospectively analyzed 12 patients who received Eculizumab in France between 2010 and 2013 for severe post-HSCT TMA. RESULTS: All 12 patients had severe TMA with neurological and/or renal involvement. Fifty-eight percent were refractory to first-line plasma exchange. At the time of TMA diagnosis, infections were present in 50% of the patients and acute graft-versus-host disease in 33%. Patients were treated with Eculizumab according to the aHUS therapeutic scheme. With a median follow-up of 14 months, hematological response and overall survival were 50% and 33%, respectively. Active acute graft-versus-host disease at TMA diagnosis was the only factor associated with worse overall survival (P = 0.009). DISCUSSION: Response rate and overall survival after Eculizumab in our cohort compare favorably with previously published data in TMA after allogeneic HSCT. Prospective trials are warranted to confirm these results. Early initiation of Eculizumab may have a favorable effect on long-term renal function and further contribute to the prolongation of survival.