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Simple Summary: In our study, we investigated immune regulation in a subtype of lymphoma called mantle cell lymphoma (MCL). Our goal was to understand how different types of immune cells, specifically T cells, behave in MCL. To do this, we combined image analysis and a technology called digital spatial profiling. We looked at tumor tissue from 102 MCL patients and analyzed different T-cell subsets. Interestingly, we found that late-stage differentiated T cells (CD57+) were more common in tumor-rich areas. These T cells also showed an increased expression of immune suppressive markers. We identified potential targets for treatment, such as CD47, IDO1, and CTLA-4. Additionally, we found that patients with sparse T-cell infiltration had an increased amount of GITR, which tentatively can be therapeutically targeted. Our findings shed light on previously unknown features of T-cell behavior in MCL. With the aim to advance the understanding of immune regulation in MCL and to identify targetable T-cell subsets, we set out to combine image analysis and spatial omic technology focused on both early and late differentiation stages of T cells. MCL patient tissue (n = 102) was explored using image analysis and GeoMx spatial omics profiling of 69 proteins and 1812 mRNAs. Tumor cells, T helper (TH) cells and cytotoxic (TC) cells of early (CD57−) and late (CD57+) differentiation stage were analyzed. An image analysis workflow was developed based on fine-tuned Cellpose models for cell segmentation and classification. TC and CD57+ subsets of T cells were enriched in tumor-rich compared to tumor-sparse regions. Tumor-sparse regions had a higher expression of several key immune suppressive proteins, tentatively controlling T-cell expansion in regions close to the tumor. We revealed that T cells in late differentiation stages (CD57+) are enriched among MCL infiltrating T cells and are predictive of an increased expression of immune suppressive markers. CD47, IDO1 and CTLA-4 were identified as potential targets for patients with T-cell-rich MCL TIME, while GITR might be a feasible target for MCL patients with sparse T-cell infiltration. In subgroups of patients with a high degree of CD57+ TC-cell infiltration, several immune checkpoint inhibitors, including TIGIT, PD-L1 and LAG3 were increased, emphasizing the immune-suppressive features of this highly differentiated T-cell subset not previously described in MCL. [ABSTRACT FROM AUTHOR]

Viral infections, including those caused by COVID-19, can produce striking morphologic changes in peripheral blood. Distinguishing between reactive changes and abnormal morphology of monocytes remains particularly difficult, with low consensus rates reported amongst hematopathologists. Here, we report a patient who developed transient monocytosis of 11.06 × 109/L with 32% promonocytes and 1% blasts during hospitalization that was secondary to severe COVID-19 infection. Three days later, the clinical status of the patient improved and the WBC had decreased to 8.47 × 109/L with 2.2 × 109/L monocytes. Flow cytometry studies did not reveal immunophenotypic findings specific for an overt malignant population. At no time during admission did the patient develop cytopenia(s), and she was discharged upon clinical improvement. However, the peripheral blood sample containing promonocytes was sent for molecular testing with an extended next-generation sequencing myeloid panel and was positive for pathogenic NPM1 Type A and DNMT3A R882H mutations. Subsequently, despite an essentially normal complete blood count, the patient underwent a bone marrow assessment that showed acute myeloid leukemia with 77% promonocytes. This case emphasizes the critical importance of a full work up to exclude acute leukemia when classical promonocyte morphology is encountered in the peripheral blood. Promonocytes are not a part of the reactive changes associated with COVID-19 and remain specific to myeloid neoplasia. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemias (AMLs) are overlapping hematological neoplasms associated with rapid onset, progressive, and frequently chemo-resistant disease. At diagnosis, classification and risk stratification are critical for treatment decisions. A group with expertise in the clinical, pathologic, and genetic aspects of these disorders developed the International Consensus Classification (ICC) of acute leukemias. One of the major changes includes elimination of AML with myelodysplasia-related changes group, while creating new categories of AML with myelodysplasia-related cytogenetic abnormalities, AML with myelodysplasia-related gene mutations, and AML with mutated TP53. Most of recurrent genetic abnormalities, including mutations in NPM1, that define specific subtypes of AML have a lower requirement of ≥ 10% blasts in the bone marrow or blood, and a new category of MDS/AML is created for other case types with 10–19% blasts. Prior therapy, antecedent myeloid neoplasms or underlying germline genetic disorders predisposing to the development of AML are now recommended as qualifiers to the initial diagnosis of AML. With these changes, classification of AML is updated to include evolving genetic, clinical, and morphologic findings. [ABSTRACT FROM AUTHOR]

B Conclusion: b Our results show that a high level of the M2 macrophage marker sCD163 is a negative prognostic factor in MCL, both in the chemoimmunotherapy and the ibrutinib/lenalidomide eras. B Introduction: b The outcome for patients with mantle cell lymphoma (MCL) has drastically improved with new treatments directed towards the tumor immune microenvironment, where macrophages play an important role. [Extracted from the article]

The first section of the bone marrow workshop of the European Association of Haematopathology (EAHP) 2020 Virtual Meeting was dedicated to pediatric myeloid neoplasms. The section covered the whole spectrum of myeloid neoplasms, including myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPN), myelodysplastic/myeloproliferative neoplasms (MDS/MPN), and acute myeloid leukemia (AML). The workshop cases are hereby presented, preceded by an introduction on these overall rare diseases in this age group. Very rare entities such as primary myelofibrosis, pediatric MDS with fibrosis, and MDS/MPN with JMML-like features and t(4;17)(q12;q21); FIP1L1::RARA fusion, are described in more detail. [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma (MCL) is an aggressive B-cell neoplasm that follows a heterogeneous clinical course. Recurrent mutations have been described, but their applicability in the clinical setting is currently limited. The main reasons are challenges in the sequencing of DNA retrieved from formalin-fixed tissue commonly used for tissue collection in clinical biobanks. In this study, we sequenced 77 samples from a population-based de novo MCL cohort to investigate the utility of targeted sequencing in guiding personalized treatment approaches. Tumors were genetically variable, and a similar genetic landscape as previous studies using non-formalin fixed samples was identified, with recurrent mutations including ATM, KMT2D, and TP53. Novel alterations that can be considered actionable and/or indicative of treatment response were also identified. Our approach shows the potential benefits of using target sequencing of formalin fixed samples to facilitate treatment selection and individualized clinical decisions in MCL. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to determine risk factors for development of acute myeloid leukemia/myelodysplastic syndromes (AML/MDS) in patients with multiple myeloma (MM). Methods: We identified all patients diagnosed with MM in Sweden from January 1st, 1958 to December 31, 2011. A total of 26 627 patients were diagnosed with MM with during the study period. Of these, 124 patients (0.5%) developed subsequent AML/MDS. For each patient with MM and a subsequent AML/MDS diagnosis, we randomly selected a matched (age, sex, and date of MM diagnosis) MM patient without a subsequent second malignancy diagnosis. Results: The cumulative melphalan exposure was significantly higher (OR = 2.8, 95% CI 1.7‐5.2; P <.001) among cases (median 988 mg; IQR 644‐1640) compared with controls (median 578 mg; IQR 360‐967). Median time to AML/MDS development was 3.8 years (IQR 2.8‐5.8). Risk of AML/MDS was not statistically altered by M protein isotype, anemia, renal failure, hypercalcemia, lytic bone lesions, or radiation therapy. Conclusion: In this nationwide population‐based study, we show that increased cumulative doses of alkylating therapy with melphalan increases the subsequent risk of developing AML/MDS in patients with MM. Given improved survival in MM patients over the last decade future studies will be important to better define long‐term risks. [ABSTRACT FROM AUTHOR]

Ever since hematopoietic cells became “events” enumerated and characterized in suspension by cell counters or flow cytometers, researchers and engineers have strived to refine the acquisition and display of the electronic signals generated. A large array of solutions was then developed to identify at best the numerous cell subsets that can be delineated, notably among hematopoietic cells. As instruments became more and more stable and robust, the focus moved to analytic software. Almost concomitantly, the capacity increased to use large panels (both with mass and classical cytometry) and to apply artificial intelligence/machine learning for their analysis. The combination of these concepts raised new analytical possibilities, opening an unprecedented field of subtle exploration for many conditions, including hematopoiesis and hematological disorders. In this review, the general concepts and progress achieved in the development of new analytical approaches for exploring high- dimensional data sets at the single- cell level will be described as they appeared over the past few years. A larger and more practical part will detail the various steps that need to be mastered, both in data acquisition and in the preanalytical check of data files. Finally, a step- by- step explanation of the solution in development to combine the Bioconductor clustering algorithm FlowSOM and the popular and widely used software Kaluza® (Beckman Coulter) will be presented. The aim of this review was to point out that the day when these progresses will reach routine hematology laboratories does not seem so far away. [ABSTRACT FROM AUTHOR]

Ever since hematopoietic cells became "events" enumerated and characterized in suspension by cell counters or flow cytometers, researchers and engineers have strived to refine the acquisition and display of the electronic signals generated. A large array of solutions was then developed to identify at best the numerous cell subsets that can be delineated, notably among hematopoietic cells. As instruments became more and more stable and robust, the focus moved to analytic software. Almost concomitantly, the capacity increased to use large panels (both with mass and classical cytometry) and to apply artificial intelligence/machine learning for their analysis. The combination of these concepts raised new analytical possibilities, opening an unprecedented field of subtle exploration for many conditions, including hematopoiesis and hematological disorders. In this review, the general concepts and progress achieved in the development of new analytical approaches for exploring high‐dimensional data sets at the single‐cell level will be described as they appeared over the past few years. A larger and more practical part will detail the various steps that need to be mastered, both in data acquisition and in the preanalytical check of data files. Finally, a step‐by‐step explanation of the solution in development to combine the Bioconductor clustering algorithm FlowSOM and the popular and widely used software Kaluza® (Beckman Coulter) will be presented. The aim of this review was to point out that the day when these progresses will reach routine hematology laboratories does not seem so far away. [ABSTRACT FROM AUTHOR]

5-Azacitidine (AZA) therapy is used in high-risk myelodysplastic syndrome (MDS) patients who often show abnormalities in their immunophenotype. We explored the potential impact of AZA on these immunophenotypic abnormalities in serial bone marrow studies performed in 81 patients from five centers. We compared the immunophenotypic features before and after therapy with AZA, established definitions consistent with flow cytometry immunophenotyping (FCI) improvement, and explored its clinical significance. After a median of 6 cycles of AZA, 41% of patients showed a FCI improvement and this finding associated with best possible clinical response (P < 0.001). FCI improvement also correlated with hematological improvement (HI) (53/78 patients; 68%), independently of their eligibility for stem cell transplantation. Among patients who achieved a HI after 6 cycles of AZA, the probability of maintaining this response at 12 cycles of AZA was twice as large (67%) for those patients who also achieved a FCI improvement after 6 cycles of AZA as compared to patients who did not (33%, P < 0.01). These findings support that monitoring of the immunophenotypic abnormalities during therapy with AZA may assist in redefining the quality of response in patients with MDS. [ABSTRACT FROM AUTHOR]

Summary: We characterised patients with mantle cell lymphoma (MCL) with poor prognosis based on differences in immune infiltration. Different expressions of the tumour cell markers Cyclin D1 and sex‐determining region Y‐box transcription factor 11 (SOX11), and the immune markers cluster of differentiation 3 (CD3), CD4, CD8, CD25, forkhead box protein P3 (FoxP3), T‐box transcription factor TBX21 (T‐bet), programmed cell death protein 1 (PD‐1), programmed‐death ligand 1 (PD‐L1) and CD163 were investigated for all‐cause mortality in 282 patients with MCL and time‐to‐progression (TTP) in 106 clinical trial patients. With increasing age, a significantly lower infiltration of CD3+ T lymphocytes was seen. T‐cell infiltration was independent of cellular tumour antigen p53 (p53) expression, Ki‐67, morphology and frequency of tumour cells. The all‐cause mortality was higher in patients with PD‐L1‐expression above cut‐off [hazard ratio (HR) 1·97, 95% confidence interval (CI) 1·18–3·25, adjusted for sex and MCL International Prognostic Index (MIPI)] and a higher frequency of CD163+ cells (continuously, HR 1·51, 95% CI 1·03–2·23, adjusting for age, sex, morphology, Ki‐67 and p53). In patients treated within the Nordic Lymphoma Group MCL2/3 trials, TTP was shorter in patients with a higher frequency of FoxP3+ cells (HR 3·22, 95% CI 1·40–7·43) and CD163+ cells (HR 6·09, 95% CI 1·84–20·21), independent of sex and MIPI. When combined a higher frequency of CD163+ macrophages and PD‐L1+ cells or high CD163+ macrophages and FoxP3+ regulatory T cells indicated worse outcome independent of established risk factors. The T‐cell infiltrate was in turn independent of molecular characteristics of the malignant cells and decreased with age. [ABSTRACT FROM AUTHOR]

Summary: Survival for patients diagnosed with mantle cell lymphoma (MCL) has improved drastically in recent years. However, patients carrying mutations in tumour protein p53 (TP53) do not benefit from modern chemotherapy‐based treatments and have poor prognosis. Thus, there is a clinical need to identify missense mutations through routine analysis to enable patient stratification. Sequencing is not widely implemented in clinical practice for MCL, and immunohistochemistry (IHC) is a feasible alternative to identify high‐risk patients. The aim of the present study was to investigate the accuracy of p53 as a tool to identify patients with TP53 missense mutations and the prognostic impact of overexpression and mutations in a Swedish population‐based cohort. In total, 317 cases were investigated using IHC and 255 cases were sequenced, enabling analysis of p53 and TP53 status among 137 cases divided over the two‐cohort investigated. The accuracy of predicting missense mutations from protein expression was 82%, with sensitivity at 82% and specificity at 100% in paired samples. We further show the impact of p53 expression and TP53 mutations on survival (hazard ratio of 3·1 in univariate analysis for both), and the association to risk factors, such as high MCL International Prognostic Index, blastoid morphology and proliferation, in a population‐based setting. [ABSTRACT FROM AUTHOR]

The percentage of blasts cells in the bone marrow (BM) of MDS patients is one of the key parameters for MDS classification and for the differential diagnosis with acute myeloid leukemia (AML). Currently, the gold standard to determine the blast percentage is conventional cytomorphology. To assess the possible impact of blast cell enumeration in BM biopsies from MDS patients on the final WHO classification using CD34 immunohistochemistry (IHC) a total of 156 BM samples from MDS and MDS-AML patients were studied and compared to blast counts by cytomorphology (CM). Eighty-nine BM aspirates were also studied by flow cytometry (FCM). Percentages of CD34+ blasts by IHC were determined blindly by two hematopathologists. Automated CD34-cell count was performed in 25 cases. Good overall agreement was found for CM and FCM with respect to critical blast thresholds (5%, 10%, 20%) (p < 0.05). However, in 17% of patients, CD34+ blast counts by IHC were higher as compared to CM with possible impact on MDS subclassification. In 7 of 21 AML patients, diagnosis was established on BM histology, while the blast percentage by CM was below the AML threshold. The assessment of CD34+ cells by IHC showed high interobserver agreement (Spearman R 0.95, p < 0.01), while automated CD34 counts were not optimal due to interference with other cellular and stromal elements. BM histology including CD34 IHC improves the diagnostic accuracy in MDS and AML. The quantification of blast cells should be based on the integration of all three methods for reliable disease classification and risk assessment. [ABSTRACT FROM AUTHOR]

Singular values are used to construct physically admissible 3-dimensional mixing matrices characterized as contractions. Depending on the number of singular values strictly less than one, the space of the 3-dimensional mixing matrices can be split into four disjoint subsets, which accordingly corresponds to the minimal number of additional, non-standard neutrinos. We show in numerical analysis that taking into account present experimental precision and fits to different neutrino mass splitting schemes, it is not possible to distinguish, on the level of 3-dimensional mixing matrices, between two and three extra neutrino states. It means that in 3+2 and 3+3 neutrino mixing scenarios, using the so-called α parametrization, ranges of non-unitary mixings are the same. However, on the level of a complete unitary 3+1 neutrino mixing matrix, using the dilation procedure and the Cosine-Sine decomposition, we were able to shrink bounds for the “light-heavy” mixing matrix elements. For instance, in the so-called seesaw mass scheme, a new upper limit on |Ue4| is about two times stringent than before and equals 0.021. For all considered mass schemes the lowest bounds are also obtained for all mixings, i.e. |Ue4|, |Uμ4|, |Uτ4|. New results obtained in this work are based on analysis of neutrino mixing matrices obtained from the global fits at the 95% CL. [ABSTRACT FROM AUTHOR]

The understanding of neutrino-nucleus interactions is crucial for the precise measurement of neutrino oscillations phenomenon. Moreover, it is important for Monte Carlo modeling of neutrinos interactions, which at this moment is simplified. For this reason, a variety of cross-section measurements on different target materials and at different neutrino beam energies are performed worldwide. The goal of this paper is to review the recent results from neutrino cross-section measurements from the T2K experiment. [ABSTRACT FROM AUTHOR]

Singular values provide a method to study mixing matrices in particle physics. The methods of unitary dilations and the cosine-sine matrix decomposition are discussed in the framework of the Standard Model neutrinos mixing with one non-standard neutrino. We show that the mixings are continuous functions of singular values. It implies that the magnitude of non-standard mixing can be estimated from below and above unambiguously from the experimentally determined interval PMNS mixing matrix. [ABSTRACT FROM AUTHOR]

The article discusses the HS-1 associated protein X-1 (HAX-1/HAX1) which was identified as a protein that interacts with HS-1, a substrate of Src family tyrosine kinases and has been shown to be involved in multiple cellular processes such as apoptosis, calcium homeostasis and cell migration. It states that HAX-1 overexpression in multiple myeloma is associated with poor survival..

Getting access to longitudinal samples from the BIO-MUSE trial followed by applying combinatorial tools of spatially resolved and single cell omics technologies, concerning endpoint II-IV, will enable unique deep molecular investigations to empower early identification of MF patients who will progress and thus allow future personalised treatment strategies, see Figure 1. Most patients with MF patients are diagnosed at an early stage with chronic characteristics and exhibit a good prognosis with a 5-year survival of 89%-98%. I Single cell RNA-sequencing. i Gene expression profiles of tumor cells and bulk T cells from peripheral blood will be analyzed by single cell RNA sequencing. [Extracted from the article]

We have developed a lymphoproliferative disorder screening tube ( LPD- ST) with the aim to provide comprehensive immunophenotyping of lymphocyte subsets with minimal need for additional testing. The LPD- ST consists of CD4/kappa FITC, CD8/lambda PE, CD3/ CD14 ECD, CD38 PC5.5, CD20/ CD56 PC7, CD10 APC, CD19 APC-A700, CD5 APC-A750, CD57/ CD23 PB and CD45 KO. The LPD- ST was validated against previously used lymphocyte subset panels in Canada (n=60) and in Sweden (n=43) and against the OneFlow™ LST (n=60). The LPD- ST panel was then implemented in clinical practice using dried monoclonal antibody reagents (Duraclone®) on 649 patient samples in Sweden. In 204 of 649 samples (31%), a monotypic B-cell population was found. Of these cases, a final diagnosis could be rendered in 106 cases (52%), and in the remainder, additional B-cell immunophenotyping was performed. In 20 (3%) samples, an aberrant T-cell population was confirmed by additional testing. Of 425 samples diagnosed as normal/reactive lymphoid tissue, 50 (12%) required additional immunophenotyping, mostly due to an abnormal CD4/ CD8 ratio. The LPD- ST tube significantly minimizes the need for additional testing, improves the turn-around time, and reduces the cost of LPD immunophenotyping. It is also suitable for investigating paucicellular samples such as cerebrospinal fluid or fine needle aspirates. [ABSTRACT FROM AUTHOR]

Objectives: Postoperative pain management is of highest interest for patients undergoing maxillofacial surgery including microvascular reconstructive surgery. Currently, there is a lack of information regarding process and outcome of postoperative pain management after microvascular reconstruction. Materials and methods: In a prospective clinical study, 31 adults were evaluated on the first postoperative day following microvascular reconstruction with a radial forearm flap using the standardized questionnaire of the Germany-wide project Quality Improvement in Postoperative Pain Management (QUIPS). It enables a standardized assessment of patients' characteristics, pain parameters, outcome and pain therapy process parameters. Results: Pain management consisted predominately of premedication with midazolam, sufentanil and metamizol intraoperatively, piritramid in the intensive care unit and metamizol, tramadol and fentanyl patches on ward. Nineteen patients (61.3 %) showed inadequate pain management with pain levels ≥4. Among other significant relations, patients exhibiting an age below the median presented significant higher levels of pain under strain ( p = .041) and maximum pain ( p = .006) as well as rate of breathing ( p = .009) and mood ( p = .006) disturbance. Performance of pain counselling showed specific impact on pain under strain ( p = .008), maximum pain ( p = .004) and satisfaction with pain intensity ( p = .001). Whether microvascular reconstruction was performed with primary or secondary intention or performance of a neck dissection did not show significant influence. Conclusions: QUIPS helped us to adequately evaluate the procedure-specific quality of postoperative management following microvascular reconstruction with a radial forearm flap. It helped us to identify a surprisingly high amount of inadequate pain management. Postoperative pain levels seem to be primarily influenced by the performed reconstruction. Clinical relevance: Establishment of a continuous and procedure-specific evaluation of postoperative pain levels should help to avoid inadequate pain management, which is widely prevalent according to the literature and our study. Preoperative pain counselling is essential and should be procedure specific to be its best. [ABSTRACT FROM AUTHOR]

X-linked lymphoproliferative disease is a rare T and NK cell immune deficiency which most frequently presents as fulminant infectious mononucleosis following infection with the Epstein-Barr virus (EBV). We report the case of a 4-year-old boy from a Spanish family presenting with severe infectious mononucleosis. In the course of the disease he developed hepatic failure, pancytopenia and neurologic impairment, leading to death after less than 2 months. The results of bone marrow biopsy and autopsy indicated a histological diagnosis of both high-grade B-cell lymphoma and virus-associated haemophagocytic syndrome, thereby confirming the simultaneous presence of two different manifestations of X-linked lymphoproliferative disease (XLP) in this patient. The family history revealed four close male relatives dying under similar circumstances, one of whom died following a vaccination against measles. Molecular genetic studies identified a novel mutation in the SH2D1A gene in several members of the family, establishing the diagnosis of XLP. Fatal EBV infection in male infants is highly indicative of XLP. Virus-associated haemophagocytic syndrome and B-cell lymphoma can occur concomitantly and may be difficult to distinguish due to their similar histological pictures. [ABSTRACT FROM AUTHOR]

Diffuse large B-cell lymphoma (DLBCL), the most common type of non-Hodgkin's lymphoma (NHL) in adults, accounts for approximately 30-40% of newly diagnosed lymphomas worldwide. Environmental factors, such as viruses and bacteria, may contribute to cancer development through chronic inflammation and the integration of oncogenes, and have previously been indicated in cervical cancer, hepatocellular carcinoma, gastric cancer and lymphoproliferative disorders. In the present study, the presence of microbial agents was analyzed in the lymphoma tissue of patients with activated B-cell like (ABC) DLBCL. The present study compared two groups of patients from geographically varied regions that possess a difference in the prevalence of viral and other microbial agents. The patient populations were from Sweden (a low endemic infectious disease region) and Egypt (a high endemic infectious disease region). A differential expression of several viruses in lymphoma tissues was noted when comparing Swedish and Egyptian patients. JC polyomavirus (JCV) was detected in Swedish and Egyptian patients and, uniquely, the complete hepatitis B virus (HBV) genome was detected only in Egyptian lymphoma patients. None of these viruses were detected in control lymph tissues from Sweden or Egypt. In total, 38% of the Egyptian patients were found to have HBV surface antigens (HBsAgs) in their serum; however, HBsAgs were not found in any of the Swedish patients. The percentage of serum HBsAgs in Egyptian patients with ABC DLBCL was significantly increased compared with the general Egyptian population (P<0.05). The present study may support a notion that viral agents, including JCV and HBV, may be involved in the tumorigenesis of DLBCL in regions of high infectious disease. [ABSTRACT FROM AUTHOR]

Objectives: To standardize diagnostic investigations for myeloproliferative neoplasms (MPNs) to increase homogeneity in patient care and to streamline diagnostic approaches in the most efficient and cost-effective manner.Methods: The development of Canadian expert consensus recommendations for the diagnosis of MPNs began with a review of the following: clinical evidence, daily practice, existing treatment guidelines, and availability of diagnostic tools. Each group member was assigned a specific topic, which they discussed with the entire group during several consensus meetings.Results: This document provides the Canadian MPN group's recommendations, proposed diagnostic algorithms, and background evidence upon which decisions were made.Conclusions: Standardization of diagnostic investigations will increase homogeneity in patient care and provide a foundation for future clinical research in this rapidly evolving therapeutic area. Streamlining diagnostic approaches in the most efficient and cost-effective manner will also result in significant cost saving for the health care system. [ABSTRACT FROM AUTHOR]

Objectives: To standardize diagnostic investigations for myeloproliferative neoplasms (MPNs) to increase homogeneity in patient care and to streamline diagnostic approaches in the most efficient and cost-effective manner. Methods: The development of Canadian expert consensus recommendations for the diagnosis of MPNs began with a review of the following: clinical evidence, daily practice, existing treatment guidelines, and availability of diagnostic tools. Each group member was assigned a specific topic, which they discussed with the entire group during several consensus meetings. Results: This document provides the Canadian MPN group's recommendations, proposed diagnostic algorithms, and background evidence upon which decisions were made. Conclusions: Standardization of diagnostic investigations will increase homogeneity in patient care and provide a foundation for future clinical research in this rapidly evolving therapeutic area. Streamlining diagnostic approaches in the most efficient and cost-effective manner will also result in significant cost saving for the health care system. [ABSTRACT FROM AUTHOR]

Small B cell lymphoid neoplasms are the most common lymphoproliferative disorders involving peripheral blood ( PB) and bone marrow ( BM). The Bone Marrow Workshop ( BMW) organized by the European Bone Marrow Working Group ( EBMWG) of the European Association for Haematopathology ( EAHP) during the XVIIth EAHP Meeting in Istanbul, October 2014, was dedicated to discussion of cases illustrating how the recent advances in immunophenotyping, molecular techniques and cytogenetics provide better understanding and classification of these entities. Submitted cases were grouped into following categories: (i) cases illustrating diagnostic difficulties in chronic lymphocytic leukaemia (CLL); (ii) cases of BM manifestations of small B cell lymphoid neoplasms other than CLL; (iii) transformation of small B cell lymphoid neoplasms in the BM; and (iv) multiclonality and composite lymphomas in the BM. This report summarizes presented cases and conclusions of the BMW and provides practical recommendations for classification of the BM manifestations of small B cell lymphoid neoplasms based on the current state of knowledge. [ABSTRACT FROM AUTHOR]

Background: Most malignant lymphomas in HIV-patients are caused by reactivation of EBV-infection. Some lymphomas have a very rapid fulminant course. HHV-8 has also been reported to be a cause of lymphoma. The role of CMV in the development of lymphoma is not clear, though both CMV and HHV-8 have been reported in tissues adjacent to the tumour in Burkitt lymphoma patients. Here we present a patient with asymptomatic HIV infection, that contracted a primary cytomegalovirus (CMV) infection and human herpes virus 8 (HHV-8) infection. Three weeks before onset of symptoms the patient had unprotected sex which could be possible source of his CMV and also HHV-8 infection He deteriorated rapidly and died with a generalized anaplastic large cell lymphoma (ALCL). Methods: A Caucasian homosexual male with asymptomatic human immunodeficiency virus (HIV) infection contracted a primary cytomegalovirus (CMV) infection and human herpes virus 8 (HHV-8) infection. He deteriorated rapidly and died with a generalized anaplastic large cell lymphoma (ALCL). Clinical and laboratory records were compiled. Immunohistochemistry was performed on lymphoid tissues, a liver biopsy, a bone marrow aspirate and the spleen during the illness and at autopsy. Serology and PCR for HIV, CMV, EBV, HHV-1-3 and 6-8 was performed on blood drawn during the course of disease. Results: The patient presented with an acute primary CMV infection. Biopsies taken 2 weeks before death showed a small focus of ALCL in one lymph node of the neck. Autopsy demonstrated a massive infiltration of ALCL in lymph nodes, liver, spleen and bone marrow. Blood samples confirmed primary CMV- infection, a HHV-8 infection together with reactivation of Epstein- Barr-virus (EBV). Conclusion: Primary CMV-infection and concomitant HHV-8 infection correlated with reactivation of EBV. We propose that these two viruses influenced the development and progression of the lymphoma. Quantitative PCR blood analysis for EBV, CMV and HHV-8 could be valuable in diagnosis and treatment of this type of very rapidly developing lymphoma. It is also a reminder of the importance of prevention and prophylaxis of several infections by having protected sex. [ABSTRACT FROM AUTHOR]

This review focuses on the most recent literature concerning flow cytometry (FCM) application for diagnosis of myelodysplastic syndrome (MDS). Aberrant FCM results have been defined as abnormalities in at least three tested features comprising at least two bone marrow (BM) cell compartments. FCM results should be interpreted together with the BM smear cytology, the morphological assessment of BM biopsy, and cytogenetic results. Including FCM in the pre-treatment assessment may provide not only diagnostic but also prognostic information. Further studies are needed to evaluate the role of FCM in individual risk assessment for MDS patients and in therapy choice and/or follow-up. [ABSTRACT FROM AUTHOR]

Objectives: This session of the Society for Hematopathology/European Association for Haematopathology Workshop focused on acute leukemias of ambiguous origin. Methods: We provide an overview of mixed-phenotype acute leukemia (MPAL) as recognized in the current World Health Organization classification and summarize diagnostic criteria for major categories of MPAL: B/myeloid, T/myeloid, B/T, and B/T/myeloid. Results: Most MPAL cases submitted were B/myeloid and T/myeloid MPAL, the most frequent types, but three cases of B/T MPAL were also submitted, and examples of all categories are illustrated. We emphasize that a comprehensive approach to immunophenotyping is required to accurately establish the diagnosis of MPAL. Flow cytometry immunophenotyping using a large panel of antibodies is needed as well as confirmatory immunohistochemical analysis and cytochemistry studies for myeloperoxidase and nonspecific esterase. We discuss technical issues in determining blast lineage and possible pitfalls in MPAL diagnosis. In particular, rare cases of B-acute lymphoblastic leukemia (B-ALL) can express myeloperoxidase but are otherwise consistent with B-ALL and should be treated as such. Last, we review the differential diagnosis between acute undifferentiated leukemia and acute myeloid leukemia with minimal differentiation. Conclusions: There was an agreement that diagnosis of MPAL can be challenging, especially if applied flow cytometry panels are not comprehensive enough. [ABSTRACT FROM AUTHOR]

Objectives: This session of the Society for Hematopathology/ European Association for Haematopathology Workshop focused on acute leukemias of ambiguous origin. Methods: We provide an overview of mixed-phenotype acute leukemia (MPAL) as recognized in the current World Health Organization classification and summarize diagnostic criteria for major categories of MPAL: B/myeloid, T/myeloid, B/T, and B/T/myeloid. Results: Most MPAL cases submitted were B/myeloid and T/myeloid MPAL, the most frequent types, but three cases of B/T MPAL were also submitted, and examples of all categories are illustrated. We emphasize that a comprehensive approach to immunophenotyping is required to accurately establish the diagnosis of MPAL. Flow cytometry immunophenotyping using a large panel of antibodies is needed as well as confirmatory immunohistochemical analysis and cytochemistry studies for myeloperoxidase and nonspecific esterase. We discuss technical issues in determining blast lineage and possible pitfalls in MPAL diagnosis. In particular, rare cases of B-acute lymphoblastic leukemia (B-ALL) can express myeloperoxidase but are otherwise consistent with B-ALL and should be treated as such. Last, we review the differential diagnosis between acute undifferentiated leukemia and acute myeloid leukemia with minimal differentiation. Conclusions: There was an agreement that diagnosis of MPAL can be challenging, especially if applied flow cytometry panels are not comprehensive enough. [ABSTRACT FROM AUTHOR]

Bone marrow (BM) tissue biopsy evaluation, including trephine biopsy and clot section, is an integral part of BM investigation and is often followed by ancillary studies, in particular immunohistochemistry (IHC). IHC provides in situ coupling of morphological assessment and immunophenotype. The number of different IHC tests that can be applied to BM trephine biopsies and the number of indications for IHC testing is increasing concurrently with the development of flow cytometry and molecular diagnostic methods. An international Working Party for the Standardization of Bone Marrow IHC was formed by the International Council for Standardization in Hematology (ICSH) to prepare a set of guidelines for the standardization of BM IHC based on currently available published evidence and modern understanding of quality assurance principles as applied to IHC in general. The guidelines were discussed at the ICSH General Assemblies and reviewed by an international panel of experts to achieve further consensus and represent further development of the previously published ICSH guidelines for the standardization of BM specimens handling and reports. [ABSTRACT FROM AUTHOR]