Assessment of Bone Microarchitecture in Patients with Systemic Mastocytosis and its Association with Clinical and Biochemical Parameters of the Disease.

Patients with systemic mastocytosis (SM) are at high risk of bone deterioration. However, the evaluation of bone microarchitecture in this disease remains unclear. We aimed to assess bone microarchitecture in patients with SM. This was a cross-sectional study of 21 adult patients with SM conducted in a quaternary referral hospital in Sao Paulo, Brazil. A healthy, age-, weight-, and sex-matched cohort of 63 participants was used to provide reference values for bone microarchitecture, assessed by high resolution peripheral quantitative computed tomography (HR-pQCT). Total volumetric bone mineral density (vBMD), cortical vBMD, and cortical thickness at the radius were significantly lower in the control group compared with the SM group (all P < 0.001). Patients with aggressive SM had significantly lower trabecular number (Tb.N) (P = 0.035) and estimated failure load (F.load) (P = 0.032) at the tibia compared with those with indolent SM. Handgrip strength was significantly higher in patients who had more Tb.N at the radius (ρ, 0.46; P = 0.036) and tibia (ρ, 0.49; P = 0.002), and lower who had more trabecular separation at the radius (ρ, -0.46; P = 0.035) and tibia (ρ, -0.52; P = 0.016). Strong and positive associations between F.load (ρ, 0.75; P < 0.001) and stiffness (ρ, 0.70; P < 0.001) at the radius, and between F.load at the tibia (ρ, 0.45; P = 0.038) were observed with handgrip strength. In this cross-sectional study, aggressive SM was more susceptible to bone deterioration compared with indolent SM. In addition, the findings demonstrated that handgrip strength was associated with bone microarchitecture and bone strength.

Differential diagnosis of bone marrow failure syndromes guided by machine learning.

The choice to postpone treatment while awaiting genetic testing can result in significant delay in definitive therapies in patients with severe pancytopenia. Conversely, the misdiagnosis of inherited bone marrow failure (BMF) can expose patients to ineffectual and expensive therapies, toxic transplant conditioning regimens, and inappropriate use of an affected family member as a stem cell donor. To predict the likelihood of patients having acquired or inherited BMF, we developed a 2-step data-driven machine-learning model using 25 clinical and laboratory variables typically recorded at the initial clinical encounter. For model development, patients were labeled as having acquired or inherited BMF depending on their genomic data. Data sets were unbiasedly clustered, and an ensemble model was trained with cases from the largest cluster of a training cohort (n = 359) and validated with an independent cohort (n = 127). Cluster A, the largest group, was mostly immune or inherited aplastic anemia, whereas cluster B comprised underrepresented BMF phenotypes and was not included in the next step of data modeling because of a small sample size. The ensemble cluster A-specific model was accurate (89%) to predict BMF etiology, correctly predicting inherited and likely immune BMF in 79% and 92% of cases, respectively. Our model represents a practical guide for BMF diagnosis and highlights the importance of clinical and laboratory variables in the initial evaluation, particularly telomere length. Our tool can be potentially used by general hematologists and health care providers not specialized in BMF, and in under-resourced centers, to prioritize patients for genetic testing or for expeditious treatment.

Diagnosis and treatment of systemic mastocytosis in Brazil: Recommendations of a multidisciplinary expert panel

ABSTRACT Introduction: Systemic Mastocytosis comprises a group of neoplastic diseases characterized by clonal expansion and infiltration of mast cells into several organs. The diagnosis and treatment of this disease may be challenging for non-specialists. Objective: Make suggestions or recommendations in Systemic Mastocytosis based in a panel of Brazilian specialists. Method and results: An online expert panel with 18 multidisciplinary specialists was convened to propose recommendations on the diagnosis and treatment of Systemic Mastocytosis in Brazil. Recommendations were based on discussions of topics and multiple-choice questions and were graded using the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence Chart. Conclusion: Twenty-two recommendations or suggestions were proposed based on a literature review and graded according to the findings.

Diagnosis and treatment of systemic mastocytosis in Brazil: Recommendations of a multidisciplinary expert panel.

INTRODUCTION: Systemic Mastocytosis comprises a group of neoplastic diseases characterized by clonal expansion and infiltration of mast cells into several organs. The diagnosis and treatment of this disease may be challenging for non-specialists. OBJECTIVE: Make suggestions or recommendations in Systemic Mastocytosis based in a panel of Brazilian specialists. METHOD AND RESULTS: An online expert panel with 18 multidisciplinary specialists was convened to propose recommendations on the diagnosis and treatment of Systemic Mastocytosis in Brazil. Recommendations were based on discussions of topics and multiple-choice questions and were graded using the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence Chart. CONCLUSION: Twenty-two recommendations or suggestions were proposed based on a literature review and graded according to the findings.

Philadelphia-positive B-lymphoblastic leukemia in a middle-income country - A real-world multicenter cohort.

Outside of clinical trials, few studies have addressed the outcomes of Ph+ acute lymphoblastic leukemia (ALL) in adults, especially from developing world. In this study, we conducted a multicenter analysis on the outcomes of patients aged > 15 years with Ph+ ALL, aiming to get to know an overview of the Brazilian experience as well as to explore baseline factors associated with relapse and mortality in our setting. Over these 10 years, patients were treated with diverse protocols, all of them always combined with a frontline tyrosine-kinase inhibitor. A total of 123 Ph+ ALL patients was included. Imatinib was the first line TKI in 97 %. The complete response rate was 79 %. The early death rate was 15 %, being associated with increasing age at diagnosis (p = 0.06). The use of intensive versus attenuated induction regimen was not associated with higher induction mortality (p = 0.99). Overall, 29 % of patients aged ≤ 60 years underwent allogeneic transplantation, 87 % in first CR. 4-year overall survival (OS) and relapse-free survival were 25 % and 24 %, respectively. The incidence of relapse (death as a competitor) was 29 %, while the non-relapse mortality was 42 %. Only age was independently associated with OS, and lactate dehydrogenase level and central nervous disease at diagnosis were related to relapse in our cohort. This is the first historical cohort multicenter study on Ph+ ALL from Brazil. Reporting these outcomes is essential to encourage public policies to expand access to new drugs and transplantation in middle-income countries.

Recruitment of highly functional SARS-CoV-2-specific CD8+ T cell receptors mediating cytotoxicity of virus-infected target cells in non-severe COVID-19

T cell immunity is crucial for the control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and has been widely characterized on a quantitative level. In contrast, the quality of such T cell responses has been poorly investigated, in particular in the case of CD8+ T cells. Here, we explored the quality of SARS-CoV-2-specific CD8+ T cell responses in individuals who recovered from mild symptomatic infections, through which protective immunity should develop, by functional characterization of their T cell receptor (TCR) repertoire. CD8+ T cell responses specific for SARS-CoV-2-derived epitopes were low in frequency but could be detected robustly early as well as late - up to twelve months - after infection. A pool of immunodominant epitopes, which accurately identified previous SARS-CoV-2 infections, was used to isolate TCRs specific for epitopes restricted by common HLA class I molecules. TCR-engineered T cells showed heterogeneous functional avidity and cytotoxicity towards virus-infected target cells. High TCR functionality correlated with gene signatures of T cell function and activation that, remarkably, could be retrieved for each epitope:HLA combination and patient analyzed. Overall, our data demonstrate that highly functional HLA class I TCRs are recruited and maintained upon mild SARS-CoV-2 infection. Such validated epitopes and TCRs could become valuable tools for the development of diagnostic tests determining the quality of SARS-CoV-2-specific CD8+ T cell immunity, and thereby investigating correlates of protection, as well as to restore functional immunity through therapeutic transfer of TCR-engineered T cells.

Prognostic assessment for chronic myelomonocytic leukemia in the context of the World Health Organization 2016 proposal: a multicenter study of 280 patients.

Knowledge on chronic myelomonocytic leukemia (CMML) patients from Argentina and Brazil is limited. Our series of 280 patients depicted an older age at diagnosis (median 72 years old), 26% of aberrant karyotypes, and a prevalence of myelodysplastic (60%) and CMML-0 subtypes (56%). The median overall survival (OS) was 48.2 months for patients in CMML-0 (Ref.), 24.7 months for those in CMML-1 (HR = 2.0, p = 0.001), and 8.8 months for patients in CMML-2 (HR = 4.6, p < 0.001). In the CMML-0 category, median OS were different between myelodysplastic and myeloproliferative subtypes (63.7 vs 21.2 months, p < 0.001); however, no differences were observed within CMML-1 and CMML-2 subtypes (24.7 vs 23.7 months, p = 0.540, and 9.1 vs 8.2 months, p = 0.160). The prognostic impact of 24 variables and 7 prognostic systems was adjusted to the WHO 2016 after validating their usefulness. Multivariate analysis were performed, and the final model revealed Hb ≥ 8 -< 10g/dL (HR 1.7), Hb < 8g/dL (HR 2.8), poor karyotypes (HR 2.1), WHO 2016-CMML-1 (HR 2.1), and CMML-2 (HR 3.5) as independent adverse clinical parameters in our cohort with a borderline influence of platelets count < 50 × 109/L (HR 1.4). We could validate several scoring systems, the WHO 2016 proposal and its prognostic capability, along with accessible covariates, on predicting the outcome in our series of CMML patients from Latin America.

A multicenter comparative acute myeloid leukemia study: can we explain the differences in the outcomes in resource-constrained settings?

Outcomes in acute myeloid leukemia (AML) are dependent on patient- and disease-characteristics, treatment, and socioeconomic factors. AML outcomes between resource-constrained and developed countries have not been compared directly. We analyzed two cohorts: from São Paulo state, Brazil (USP, n = 312) and Oxford, United Kingdom (OUH, n = 158). USP cohort had inferior 5-year overall survival compared with OUH (29% vs. 49%, adjusted-p=.027). USP patients have higher early-mortality (23% vs. 6% p<.001) primarily due to multi-resistant Gram-negative bacterial and fungal infections. USP had higher 5-year cumulative incidence of relapse (60% vs. 50%, p=.0022), were less likely to undergo hematopoietic stem cell transplant (HSCT) (28% vs. 75%, p<.001) and waited longer for HSCT (median, 23.8 vs. 7.2 months, p<.001). Three-year survival in relapsed patients was worse in USP than OUH (10% vs. 39%, p<.001). Our study indicates that efforts to improve AML outcomes in Brazil should focus on infection prevention and control, and access to HSCT.

Single-cell RNA sequencing reveals in vivo signatures of SARS-CoV-2-reactive T cells through 'reverse phenotyping'

The in vivo phenotypic profile of T cells reactive to severe acute respiratory syndrome (SARS)-CoV-2 antigens remains poorly understood. Conventional methods to detect antigen-reactive T cells require in vitro antigenic re-stimulation or highly individualized peptide-human leukocyte antigen (pHLA) multimers. Here, we used single-cell RNA sequencing to identify and profile SARS-CoV-2-reactive T cells from Coronavirus Disease 2019 (COVID-19) patients. To do so, we induced transcriptional shifts by antigenic stimulation in vitro and took advantage of natural T cell receptor (TCR) sequences of clonally expanded T cells as barcodes for reverse phenotyping. This allowed identification of SARS-CoV-2-reactive TCRs and revealed phenotypic effects introduced by antigen-specific stimulation. We characterized transcriptional signatures of currently and previously activated SARS-CoV-2-reactive T cells, and showed correspondence with phenotypes of T cells from the respiratory tract of patients with severe disease in the presence or absence of virus in independent cohorts. Reverse phenotyping is a powerful tool to provide an integrated insight into cellular states of SARS-CoV-2-reactive T cells across tissues and activation states.

Toxicity Profile of PEG-Asparaginase in Adult Patients With Acute Lymphoblastic Leukemia in Brazil: A Multicenter Cross-Sectional Study.

BACKGROUND: Currently, pediatric-inspired regimens are commonly applied to adults with acute lymphoblastic leukemia (ALL) after the recent recognition that these protocols improve survival. While asparaginase in whatever available formulation is a key component of modern treatment of ALL, many adult oncologists and hematologists struggle to deal with its particular toxicities in clinical practice. We reviewed toxicity outcomes of pegylated asparaginase (PEG-ASP) in adults with ALL treated in 3 reference centers in Brazil. PATIENTS AND METHODS: This was a cross-sectional retrospective chart-review study encompassing patients aged 15 years and older diagnosed with ALL or ambiguous-lineage leukemia who received at least one dose of PEG-ASP, regardless of the adopted regimen. RESULTS: A total of 57 patients were included (age range, 15-57 years). Most patients (70%) received 2000 IU/m2 as the initial dose, by intravenous route (72%). The incidence of thromboembolic events was 17.5%, and the main site was cerebral venous sinus (4/10). Thrombosis was more frequent in patients receiving second-line treatment. In obese patients, grade 3 hepatotoxicity and hyperbilirubinemia were more common. Clinical pancreatitis (grade 3 or higher) was found in 2 of 57 cases. PEG-ASP had to be discontinued in 19.3% of exposed patients (11/57). CONCLUSION: By reviewing the medical charts of adult patients with ALL from 3 reference centers, we found that our incidence of thrombotic and hepatic adverse events is similar to those reported in other trials involving PEG-ASP. Usually these effects should not preclude further use of the drug because most events are manageable in routine clinical practice.

Integrating clinical features with genetic factors enhances survival prediction for adults with acute myeloid leukemia.

The 2017 European LeukemiaNet 2017 acute myeloid leukemia (AML) risk stratification (ELN2017) is widely used for risk-stratifying patients with AML. However, its applicability in low- and middle-income countries is limited because of a lack of full cytogenetic and molecular information at diagnosis. Here, we propose an alternative for risk stratification (the Adapted Genetic Risk [AGR]), which permits cytogenetic or molecular missing data while retaining prognostic power. We first analyzed 167 intensively treated patients with nonacute promyelocytic leukemia AML enrolled in São Paulo, Brazil (Faculdade de Medicina da Universidade de São Paulo), as our training data set, using ELN2017 as the standard for comparison with our AGR. Next, we combined our AGR with clinical prognostic parameters found in a Cox proportional hazards model to create a novel scoring system (survival AML score, SAMLS) that stratifies patients with newly diagnosed AML. Finally, we have used 2 independent test cohorts, Faculdade de Medicina de Ribeirão Preto (FMRP; Brazil, n = 145) and Oxford University Hospitals (OUH; United Kingdom, n = 157) for validating our findings. AGR was statistically significant for overall survival (OS) in both test cohorts (FMRP, P = .037; OUH, P = .012) and disease-free survival in FMRP (P = .04). The clinical prognostic features in SAMLS were age (>45 years), white blood cell count (<1.5 or >30.0 × 103/µL), and low albumin levels (<3.8 g/dL), which were associated with worse OS in all 3 cohorts. SAMLS showed a significant difference in OS in the training cohort (P < .001) and test cohorts (FMRP, P = .0018; OUH, P < .001). Therefore, SAMLS, which incorporates the novel AGR evaluation with clinical parameters, is an accurate tool for AML risk assessment.

Clinical impact of dysplastic changes in acquired aplastic anemia: A systematic study of bone marrow biopsies in children and adults.

Aplastic anemia (AA) is a rare disorder characterized by suppression of bone marrow function, which can progress to myelodysplastic syndrome (MDS) or to acute myeloid leukemia (AML). To determine if there are characteristics in bone marrow biopsies in children and adults previously diagnosed with acquired AA, which could predict progression to MDS, we evaluated 118 hypocellular bone marrow biopsies from adults (76 patients) and children (42) diagnosed initially with acquired AA previously to any treatment. Histology was reviewed according to a detailed protocol including Bennett and Orazi criteria for hypocellular myelodysplastic syndrome (h-MDS) and Bauman et al. criteria for refractory cytopenia of childhood (RCC). Twelve patients (10.2%; 6 children and 6 adults) progressed to MDS after a median time of 56 months. Criteria described by Bennett and Orazi suggestive of h-MDS in bone marrow biopsies were detected in 16 cases (13.5%; 8 adults and 8 children), and none in patients that progressed to MDS/AML. Twenty adults' biopsies (26.3%) had the histological criteria used for the diagnosis of pediatric RCC, and none showed MDS/AML evolution. Ten children (23.8%) were reclassified morphologically as RCC, and only one progressed to MDS. In this population with acquired aplastic anemia (AAA), no histological/immunohistochemical (H/IHC) bone marrow findings could discriminate patients with higher risk for myeloid clonal progression, which questions the diagnosis of h-MDS/RCC based only on the finding of dysplasia in the cases without increased blasts and/or the characteristic genetic abnormalities.

Patterns of Aging Biomarkers, Mortality, and Damaging Mutations Illuminate the Beginning of Aging and Causes of Early-Life Mortality.

An increase in the probability of death has been a defining feature of aging, yet human perinatal mortality starts high and decreases with age. Previous evolutionary models suggested that organismal aging begins after the onset of reproduction. However, we find that mortality and incidence of diseases associated with aging follow a U-shaped curve with the minimum before puberty, whereas quantitative biomarkers of aging, including somatic mutations and DNA methylation, do not, revealing that aging starts early but is masked by early-life mortality. Moreover, our genetic analyses point to the contribution of damaging mutations to early mortality. We propose that mortality patterns are governed, in part, by negative selection against damaging mutations in early life, manifesting after the corresponding genes are first expressed. Deconvolution of mortality patterns suggests that deleterious changes rather than mortality are the defining characteristic of aging and that aging begins in very early life.

Outcomes and second neoplasms in hairy cell leukemia: A retrospective cohort.

Hairy cell leukemia (HCL) is a rare chronic B-cell lymphoproliferative disease which is treated on the basis of small studies, making the literature still scarce of reports, especially of those conducted in Latin America. Here we intend to describe clinical characteristics, rates of response, survival and second neoplasms in HCL patients treated in a reference center in Brazil. All patients diagnosed with HCL between July/1987 and Jun/2018 were included in this analysis. Fifty-four patients were included in this analysis. Median age at diagnosis was 55 years (range, 26-88), with 37% being above 60 years-old. Most patients were treated with cladribine in our cohort (n = 36; 68%), administered through intravenous continuous infusion. Remaining patients were firstly managed with splenectomy (n = 7; 13%), IFN (n = 6; 11%) and rituximab (n = 2; 4%). In a univariate analysis, platelet count and B2M level at diagnosis were statistically associated with CR achievement (p = 0.004 and p = 0.024, respectively). A median follow-up time of 9 years was calculated. Estimated 10-year overall survival was 91.1% (95% confidence interval, 77-97). In this cohort, 10 patients had any second neoplasm, diagnosed before or after HCL. Regarding the sites of cancer, 69% were of skin - 8/16 carcinoma-type and 3/16 melanoma-type. Our response and survival data are similar to those reported by literature, which reaffirms the role of purine analogs in current HCL management. With a very long follow-up we also have observed a high incidence of second neoplasm.

Flow cytometry "Ogata score" for the diagnosis of myelodysplastic syndromes in a real-life setting. A Latin American experience.

INTRODUCTION: Flow cytometry (FC) is a helpful tool for the diagnosis of myelodysplastic syndrome (MDS). Different FC score systems have been developed. The "Ogata score" is a simple diagnostic score that has been validated having a sensitivity of 69% and a specificity of 92% in low-risk MDS. We aimed to study the feasibility and the utility of the "Ogata score" for the diagnosis of MDS among Latin America (LA) Laboratories. METHODS: This is a case and control study conducted in LA institutions members of Grupo Latinoamericano de Mielodisplasia (GLAM). A total of 146 MDS patients and 57 control patients were included. "Ogata score" was calculated. RESULTS: The sensitivity of "Ogata score" was 75.6% (95% CI, 66.8-81.3), specificity was 91.2% (95% CI, 79.7-96.7), PPV was 95.6% (95% CI, 88.5-98.3), and NPV was 65.4% (95% CI, 49.1-71.9). In low/intermediate-1 IPSS patients group, the sensitivity was 70.1% (95% CI, 60.2-78.2), specificity was 91.2% (CI-95%, 79.7-96.7), PPV was 94.2% (95% CI, 86.4-97.8), and NPV was 62.1% (95% CI, 53.0-78.7). In the group of patients "without MDS specific markers" (patients without ring sideroblasts, blast excess, or chromosomal abnormalities), the sensitivity was 66.7% (CI-95%, 55.8-76.0), specificity was 91.2% (95% CI, 79.7-96.7), PPV was 92.3% (95% CI, 82.2-97.1), and NPV was 63.5% (95% CI, 51.9-73.5). CONCLUSIONS: The diagnostic power found in this study was similar to the reported by Della-Porta et al. Also in LA, the analysis was made in modern equipment with acquisition of at least 100 000 events which permits a good reproducibility of the results.