ALBERT

Description: The success of control programs for mosquito-borne diseases can be enhanced by crucial information provided by models of the mosquito populations. Models, however, can differ in their structure, complexity, and biological assumptions, and these differences impact their predictions. Unfortunately, it is typically difficult to determine why two complex models make different predictions because we lack structured side-by-side comparisons of models using comparable parameterization. Here, we present a detailed comparison of two complex, spatially explicit, stochastic models of the population dynamics of Aedes aegypti , the main vector of dengue, yellow fever, chikungunya, and Zika viruses. Both models describe the mosquito's biological and ecological characteristics, but differ in complexity and specific assumptions. We compare the predictions of these models in two selected climatic settings: a tropical and weakly seasonal climate in Iquitos, Peru, and a temperate and strongly seasonal climate in Buenos Aires, Argentina. Both models were calibrated to operate at identical average densities in unperturbed conditions in both settings, by adjusting parameters regulating densities in each model (number of larval development sites and amount of nutritional resources). We show that the models differ in their sensitivity to environmental conditions (temperature and rainfall) and trace differences to specific model assumptions. Temporal dynamics of the Ae. aegypti populations predicted by the two models differ more markedly under strongly seasonal Buenos Aires conditions. We use both models to simulate killing of larvae and/or adults with insecticides in selected areas. We show that predictions of population recovery by the models differ substantially, an effect likely related to model assumptions regarding larval development and (direct or delayed) density dependence. Our methodical comparison provides important guidance for model improvement by identifying key areas of Ae. aegypti ecology that substantially affect model predictions, and revealing the impact of model assumptions on population dynamics predictions in unperturbed and perturbed conditions.

Description: Classic Hodgkin Lymphoma (cHL) is a germinal center derived lymphoma with 8,500-9,000 new cases/year diagnosed in the US. Despite 90% stage I cHL patients can respond to current systemic therapy, this drops to 60%, when diagnosed in advanced stages. Furthermore, 20-30% of diagnosed patients, would be refractory or would relapse and have a poor prognosis. Refractory and relapsed disease (RRD) is currently the challenge when treating cHL patients. There is no specific therapy to offer rather than rescue chemotherapy schemes, which fails in 50% of the cases and associates with high risk severe toxicity. This highlights the need to deeper understand the cHL molecular biology, the screening for molecular markers suitable to identify the risk of refractory and relapse disease and specific therapeutic directed-targets. We have previously reported that the alternative NFkB pathway, mediated by Rel-B and NIK (NFkB Inducing Kinase), plays an important role in cHL survival. Its constitutive activation sustains high BCL2 expression levels and seems to be involved in the RRD. BCL2 was found as a specific Rel-B target gene in cHL cells by ChIP-Seq (Chromatin Immunoprecipitation sequencing) and expression arrays. BCL2 exogenous expression was enough to partially rescue the death induce in cHL cells, which highlight the relevance of this alternative NFkB pathway target gene. Since the BCL2 data was obtained in human cHL cell lines established from patients with refractory and relapsed disease, we decided to analyze whether mediators of this pathway and BCL2 could be useful as prognosis markers and would represent potential targetable factors in both refractory and relapsed disease. We analyzed NIK and BCL2 citoplasm expression in Hodgkin Reed-Sternberg cells (HRS) in the lymph node biopsies of 113 cHL naïve of therapy patients by inmunohistochemistry [52 female Md age and (range) 36 (6-88), 61 male 40.7 (9-78)]. The follow-up period range from 6 to 136 months. The univariate analysis showed no correlation between NIK or BCL2 expression and the prognosis clinical and pathological parameters, including the PET Scan indicated at the end of the first line treatment, neither the molecular markers routinely assayed. The statistical significance was maintained in multivariate analysis (Logistic and Cox Regression p=0.01). NIK expression did not associate with prognosis but the BCL2 expression level correlated with lack of response to conventional therapy and both early and late disease progression. The survival analysis, using the Kaplan-Meir curves, showed that patients with ≥60% positive HRS cells had a shorter disease-free survival (DFS) [Log Rank Test (Mantel Cox) p=0.002] and a reduced overall survival (OS) [Log Rank Test (Mantel Cox) p=0.02]. L1236, U-H01, KM-H2, SUPDH1 and L540, human cHL cell lines that express BCL2 protein, were sensitive to venetoclax, a specific BCL2 inhibitor. The drug induced a cell cycle arrest in S-Phase when treated with 1uM each 24 hours during 10 days, as compared to wild type cells and cells treated with the vehicle. In summary, we found that the alternative NFkB pathway plays a role in the refractory and relapsed classic Hodgkin Lymphoma disease, being BCL2 one of its key downstream target genes. BCL2 can be used as a prognosis marker determined by routine immunohistochemistry at diagnosis of the primary disease. BCL2 expression correlated with refractory disease to first line conventional therapy and disease progression. Based on the venetoclax effect in cHL cell lines we believe BCL2 directed-therapy in cHL should be considered in the subgroup of cHL patients that express this protein in ≥60% HRS cells in the lymph node biopsy performed at diagnosis. Disclosures No relevant conflicts of interest to declare. OffLabel Disclosure: venetoclax used to specifically block BCL2.

Description: Introduction. Diffuse large B cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphomas (NHL). The use of chemoimmunotherapy (R-CHOP) in DLBCL has improved Overall Survival (OS). However, there are among 45-55% of patients who will die due to relapse, progression (refractoriness) or toxicity to treatment. Genomic classifications are difficult to use in clinical practice, especially in lain America, due to the need of trained personnel and cost. So, we continue using the International Prognostic Index (IPI) and its variations (e.g. revised-IPI, NCCN-IPI) for prognostic purposes. However, other biological variables have been reported to be prognostic, such as serum beta-2-microglobulin (B2M), lymphocyte/monocyte ratio (LMR), neutrophil/lymphocyte ratio (NLR), platelets/lymphocyte ratio (PLR) and serum albumin (SA). These factors have been associated with burden of disease, inflammation and nutritional status. Aim. Therefore, we performed a retrospective analysis of the databases of two Latin American groups to determine which biological variable is the most powerful factor prognostic of OS. Methods. A total of 1,250 patients were analyzed from two databases [(Grupo de Estudio para el Linfoma Mexicano (GELMEX) and the Grupo de Estudio para el Linfoma Latino Americano (GELL)], where 525 patients met the following inclusion criteria: DLBCL diagnosis by immunochemistry; complete data on absolute lymphocyte, absolute monocyte, absolute neutrophil and absolute platelet count, serum B2M and SA; and complete data on traditional variables for calculating risk groups for IPI, NCCN-IPI & R-IPI. The LMR, NLR and PLR was obtained. We evaluated the AUC of the biological variables and the differences among each one of them (including cut-off). Kaplan-Meier curves (KMC) were estimated and subsequently, the inference of OS was evaluated by Hazard Ratio (HR) Cox-regression in univariate/multivariate analyses by forward model. All variables with p3.2 mg/dL vs. ≤3.2 mg/dL) were 72% vs 34% (Log Rank p

Description: Introduction: Activated factor XIII (FXIII) stabilizes fibrin clots at the end of the coagulation cascade by bridging fibrin molecules. Disproportionate surgery related bleeding has been reported in association with FXIII deficiency, in patients with normal coagulopathies screening tests, and without a history of previous bleedings. Methods: Retrospective case series. We performed immunological factor XIIIA (FXIIIA) studies in the inpatient setting of the Hospital Italiano de Buenos Aires, between January 2014 and March 2016. FXIIIA below 50% were considered deficient. Patients with suspicion of congenital Factor XIII deficiency or 2 years old or less were excluded. Descriptive statistics were used. Populations were compared with chi-square, Fisher and T test, or Mann Whitney tests with Stata13 software. Results: FXIII was studied in 52 patients; 37 of these (26 females and 11 males) met inclusion and exclusion criteria. Median age was 43 years (range 9-81). Twenty two patients were studied because of disproportionate surgery related bleeding, 11 because of spontaneous bleeding; and 4 not specified. All patients presented normal coagulopathies screening tests, normal Von Willebrand factor and ristocetine cofactor activity and normal platelet function tests. Eleven patients (30%) had FXIIIA less than 50%. Statistically significant differences between groups were found for median drop in hematocrit points [3.5 (IQR 3-10) vs 1.5 (IQR 0-2, p=0.02)] and median number of red cell units transfused [4 (IQR 0-6) vs 0 (0-2), p=0.01]. Differences in rates of minor and major bleedings were not statistically significant. Only one patient of eleven presented FXIII deficiency associated spontaneous bleeding vs 8 out of 20 patients in the postsurgical setting. FXIII concentrate was used in two patients to treat persistent bleeding, resolving in less than 24 hours. Three patients died, none because of bleeding. Five of the 11 patients with FXIII deficiency returned to normal values when FXIII assay was repeated away from acute setting. Discussion: FXIII acquired deficiency is associated with disproportionate bleeding in postsurgical setting in patients without apparent coagulation defects. FXIII deficiency could be underdiagnosed. Patients with FXIII deficiency in our series had more hematocrit drop and more transfusion requirements. We found no association with spontaneous bleeding. Alltough deficiency could be transient, treatment with FXIII concentrate could be useful to manage serious, persistent or life threatening bleedings. Disclosures No relevant conflicts of interest to declare.

Description: Background : Adult T-cell leukemia/lymphoma (ATLL) is an aggressive, peripheral T-cell neoplasm associated with the human T-cell leukemia virus type 1 (HTLV-1). HTLV-1 infects up to 10 million people worldwide and is most endemic in Southwestern Japan, the Caribbean basin, South America and Western Africa. In Latin America, highest prevalence is found in Haiti, Jamaica, Dominican Republic, Brazil and Peru. ATLL has a poor prognosis, with shorter overall survival (OS) relative to other peripheral T-cell lymphomas. Although current prognostic models require extensive radiologic and laboratory investigations, oftentimes they are not readily available in most Latin American countries, hence, a simple prognostic model is useful. We aim to identify and then validate a simple clinical prognostic model for ATLL in the Latin American population by analyzing clinical parameters and only laboratory tests that are widely available across Latin American countries. Patients and Methods : We retrospectively analyzed patients (pts) diagnosed with ATLL between January 1987 and December 2018. Aggressive ATLL cases were classified according to the Shimoyama criteria into acute (A) and lymphomatous (L). Cox regression modeling was performed on several clinical and laboratory parameters in two independent cohorts: first, a learning cohort (LC) of ATLL pts diagnosed and managed at two tertiary hospitals in Chile and Peru, and then a cohort of ATLL pts from a tertiary hospital in Miami was used to validate the model (validation cohort, VC). OS curves were estimated using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate Cox proportional-hazard regression models were fitted. Results : A total of 149 pts (A=55, L=94) in the LC, and 101 pts (A=58, L=43) in the VC were identified, with 101 and 94 pts receiving therapy in each cohort, respectively. Clinical features are shown in Table 1. In both cohorts, there was a young (

Description: Introduction Estimated incidence of cHL in Argentina is 842 cases/year (Globocan 2018). There is no local data regarding response rates (RR) to FL. GATLA (Grupo Argentino de Tratamiento de Leucemia Aguda) reported 3 years progression free survival (PFS) rates of 90% and overall survival (OS) of 98% regardless of stage. HL has a high cure rate; 10% are primary refractory and 30% relapse after achieving complete remission (CR). In stage I-IIa, 5 years OS is estimated around 90% and 60% in stage IV (Ann Hematol 2019). Objectives Primary: To learn the RR, PFS and associated variables after FL of cHL in public (PuI) and private institutions (PrI) in Argentina. Secondary: To learn the OS rates. To study epidemiological characteristics of the patients (Pts) in participating institutions and reveal differences which may affect the response to treatment. Materials and methods Retrospective analysis of consecutive Pts with diagnosis of cHL from 1/1/2008 to 2/1/2019 with available follow up data. Descriptive statistics was performed in clinical variables and histopathological findings. Quantitative variables were expressed as median an interquartile range (IQR) and qualitative variables as total number and percentage (%). Survival rates were estimated by the Kaplan-Meier method and compared by the log-rank test. OS was measured from the date of diagnosis to date of death or last follow-up visit. Results 520 Pts from 7 PuI and PrI in Buenos Aires and Rosario were examined. 22 Pts had nodular lymphocyte predominant HL. Data on the 498 Pts with cHL is presented. Median follow up: 37.4 months (CI95% 17.7-63.5). Pts characteristics: Table 1. The median time from diagnosis to FL was 22 days (IQR 14-42), significantly shorter in PrI (32.5 (IC95% 27-38) vs. 49.3 (IC95% 38.5-60.2); p=0.0027). 96.5% of Pts received ABVD as FL, dose modifications or transitory suspension were required in 17.1%, and 82.1% received all cycles properly. CR was achieved in 83.4% of Pts and partial remission (PR) in 6.3%. The % achieving CR was higher in PrI; more PR were achieved in PuI. 10.3% had progressive disease (PD) at the end-of FL. 85.4% (n=373) had negative end-of-treatment FDG-PET results (DS1-3). Interim PET scan was performed in 70% of Pts (n=357), with 83.8% achieving metabolic CR but only 15.5% (n=70) being treated with response-adapted strategies (6.5% deescalated to AVD). Regarding hematologic toxicity, anemia, neutropenia and thrombocytopenia were found in 28.5%, 56.4% and 7.2% of Pts, respectively. Febrile neutropenia was reported in 9 Pts. 28.6% developed non-hematologic toxicities (41/144 pulmonary toxicity). 51 Pts had primary refractory disease and 69 (14%) relapsed during follow-up (median time to relapse 4.4 months (CI95% 0-13)). 65 Pts died (12.5%), 34 due to lymphoma progression and the remaining 31 due to toxicity. 2 years OS rate was 91% (CI95% 88% - 94%) and 85% at 5 years (CI95% 80% - 89%). There was no difference in OS between PrI and PuI (p=0.27); every day of delay in the beginning of FL increased 0.89 (IC95% 0.6-1.8) the risk of achieving PR or PD at the end of FL. 5 years PFS rate was 76% (CI95% 70-81) (figure 1-2: OS according to risk group and PFS). Outcomes were statistically better in women, age younger than 60, non-bulky disease, absence of extranodal disease or risk factors such as leukocytosis, lymphopenia and hipoalbuminemia. Pts with normal ESD, stage I-III, early favorable and advanced favorable stages and Charlson score

Description: Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most frequent subtype of lymphoma in the world and corresponds to a heterogeneous entity, both from the clinical and molecular point of view, being its prognosis of survival very variable The IPI and the NCCN-IPI are powerful risk-stratification tools in patients with DLBCL. Although the IPI risk score is widely used, it doesn't discriminate very high risk patients. In 2014 the NCCN-IPI was published. It has shown a better discrimination of these patients in Asia, Europe and USA. GELL is a recently formed group of study in lymphomas from Latin America that includes eleven countries. The aim of this study was to validate whether the NCCN-IPI is of prognostic value in Latin-American patients with DLBCL. Methods: We included patients with a diagnosis of DLBCL treated at different institution between 2012-2013. IRB approval was obtained before the collection of the data. Pathological samples were reviewed at each participating institution to confirm the diagnosis. Pertinent clinical data were collected through chart review and are presented using descriptive statistics. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate Cox proportional-hazard regression models were fitted to evaluate hazard ratio (HR) for overall survival (OS). Results: A total of 329 patients with the diagnosis of DLBCL were included in this analysis. The median age at diagnosis was 64 years (range 18-83 years) with a slight female predominance (54%). Clinically, 59% of patients were 60 or older, 34% presented with ECOG 〉1, 29% with elevated serum LDH, and 70% with extranodal disease; 49% had stage I/II and 51% had stage III/IV. The IPI score distribution was low-risk in 36% of patients, low-intermediate in 25%, high-intermediate in 22% and high-risk 17%. The NCCN-IPI score distribution was low risk in 17%, low-intermediate in 42%, high intermediate in 30% and high risk in 11%. 89% of patients received standard R-CHOP, 2% received R-miniCHOP, and 9% received other regimens. The overall response rate was 83%; 69% had complete response and 14% had partial response. The 5-year overall survival (OS) rate was 65%. DLBCL patients with low, low-intermediate, high-intermediate and high risk NCCN-IPI had 5-year OS rates of 89%, 71%, 55% and 38%, respectively (p

Description: Despite 90% stage I Hodgkin Lymphoma (HL) patients can respond to current systemic therapy, this drops to 60%, when diagnosed in advanced stages. Nevertheless and independently of the lymphoma stage, the real challenge when treating these patients, is the refractory and relapsed disease. There is no molecular biomarker to identify patients that would be non-responsive to conventional treatment or that would relapse. Furthermore, rescue chemotherapy schemes for refractory and relapsed patients, associate with acute and late toxicity high risk. This highlights the need to deeper understand the HL molecular biology and the screening for predictive biomarkers as well as potential therapeutic directed-targets. We have previously reported that HL relies on the alternative NFkB pathway, mediated by RelB and NIK, to survive. Depletion of either RelB or NIK by shRNAs or pharmacological NIK inhibitors induce HL cell death. ChIP-Seq analysis uncovered RelB target genes showing RelB bound to BCL2 promoter. A significant downregulation of BCL2 mRNA and protein levels, following RelB or NIK knockdown was observed, indicating that RelB regulates BCL2 expression in human HL cell lines. Our molecular studies suggested that NFkB alternative pathway constitutive signaling could at least partially explain the non-responding HL cases. We aimed to analyze whether mediators of this pathway could be useful as predictive biomarkers and would represent potential targetable factors in both refractory and relapsed patients. We analyzed NIK and BCL2 citoplasm expression in Hodgkin Reed-Sternberg cells (HRS) in lymphatic node biopsies of 96 patients by inmunohistochemistry [50 female Md age and (range) 59 (6-82), 46 male 42 (9-78)]. The univariate analysis showed no correlation between NIK or BCL2 expression and the prognosis clinical and pathological parameters, neither the molecular markers routinely assayed. A positive correlation was found between NIK and BCL2 expression (p=0.01). NIK and BCL2 correlated with lack of response to conventional therapy and both early and late disease progression. The analysis of survival, applying the Kaplan-Meier Curves, showed 〉 60% NIK positive HRS cells associated with shorter Disease Free Survival (DFS) [Log Rank Test (p=0.000)] and predicted overall survival (OS) as well [Log Rank Test (p=0.01)]. Furthermore, 〉 60% BCL2 positive HRS cells correlated with poor prognosis in terms of OS [Log Rank Test (p=0.002)]. The statistical significance was maintained in the multivariate analysis [Cox Regression and Logistic Regression (p=0.001)]. NIK and BCL2 performed successfully as useful predictive markers to identify refractory or risk of relapse HL patients at diagnosis. They represent attractive molecules to further analyse their potential as directed-therapy targets, since we have already reported that HL is sensitive to NIK inhibitors and BCL2 blockers have already been approved for clinical use in other hematological pathologies. Disclosures Zerga: Bristol Myers Squibb: Other: Conference fees; Janssen: Other: Conference fees; Roche: Other: Conference fees; Takeda: Other: Conference fees.

Description: Introduction: Diffuse large B-Cell Lymphoma (DLBCL) is the most frequent subtype of lymphoma in the world. The IPI score is a powerful risk-stratification tool in patients with DLBCL. The neutrophil-to-lymphocyte ratio (NLR) has shown to be prognostic in patients with DLBCL in Asia, Europe and USA. The GELL is a recently formed group for the study of lymphomas in Latin America composed by large institutions from eleven countries. The aim of this study was to evaluate whether the NLR is a prognostic factor in Latin American patients with DLBCL. Methods: We included patients with a pathological diagnosis of DLBCL who were diagnosed and treated at our institution between 2012-2013. IRB approval was obtained prior to research, and pathological samples were reviewed by hematopathologists at each of the participating institutions to confirm the diagnosis. Pertinent clinicopathological data were collected through chart review and are presented using descriptive statistics. The NLR was calculated by dividing the absolute neutrophil by the absolute lymphocyte count and dichotomized in NLR≥4 and NLR1, 29% had elevated LDH, and 70% had extranodal disease; 49% had early stage and 51% had stage III and IV. The IPI score was low risk in 36%, low-intermediate in 25%, high intermediate in 22% and high risk in 17%. 41% of patients had NLR ≥4. 89% of patients received standard R-CHOP, 2% received R-miniCHOP and 9% received other regimens. The overall response rate as 83%; 69% had complete response and 14% had partial response. The median follow-up for the entire group was 5 years (95% CI 4.9-5.4 years). The 5-year overall survival (OS) rate for the entire group was 65%. The 5-year OS rates for patients with NLR ≥4 and

Description: Introduction: Peripheral T cell lymphoma (PTCL) is a very heterogenous disease and corresponds to approximately 15% of all non-Hodgkin lymphoma cases. PTCL is divided into several subtypes, however, PTCL not otherwise specified (PTCL-NOS) is the most frequent, with a proportion of 26% of all PTCL cases. There is a lack of demographic and clinical data about PTCL-NOS in middle- and low-income countries, where patients' access to early diagnosis and otherwise standard care might be suboptimal. The objective of this study is to describe the population of PTCL-NOS patients in Latin America, specifically from the countries conforming the "Grupo Latinoamericano de Linfomas" (GELL), in order to better understand clinical behavior and find possible prognostic factors that might prognosticate overall survival (OS). We specifically evaluated the neutrophil/lymphocyte ratio (NLR) and serum albumin as potential prognostic factors. Methods: An observational, retrospective and analytical study was conducted during the period from January 2000 through January 2018. A total of 200 Latin American patients with a pathological diagnosis of PTCL-NOS were included. Clinical data were gathered from clinical records. NLR ≥4 and serum albumin ≤3.5 g/dl were considered adverse prognostic factors. Median Overall Survival (mOS) and 5-year Overall Survival (5y-OS) rates were estimated using the Kaplan-Meier method. Univariate and multivariate Cox proportional-hazard regression analyses were performed to identify adverse prognostic factors for OS. Data were analyzed and interpreted using STATA 15. Results: A total of 200 patients with a diagnosis of PTCL-NOS were included. 50% of patients were ≥60 years, 57% were male, 50% had ECOG ≥2, 40% had elevated serum Lactate Dehydrogenase (LDH) level, 70% showed stage III/IV disease, bone marrow involvement was present in 37% of patients, B symptoms in 65%, 33% presented with hemoglobin levels