Search

The survival fraction of epithelial HaCaT cells was analysed to assess the biological damage caused by intraoperative radiotherapy electron beams with varying energy spectra and intensities. These conditions were achieved by irradiating the cells at different depths in water using nominal 6 MeV electron beams while consistently delivering a dose of 5 Gy to the cell layer. Furthermore, a Monte Carlo simulation of the entire irradiation procedure was performed to evaluate the molecular damage in terms of molecular dissociations induced by the radiation. A significant agreement was found between the molecular damage predicted by the simulation and the damage derived from the analysis of the survival fraction. In both cases, a linear relationship was evident, indicating a clear tendency for increased damage as the averaged incident electron energy and intensity decreased for a constant absorbed dose, lowering the dose rate. This trend suggests that the radiation may have a more pronounced impact on surrounding healthy tissues than initially anticipated. However, it is crucial to conduct additional experiments with different target geometries to confirm this tendency and quantify the extent of this effect.

For the treatment of Multiple Myeloma, proteasome inhibitors are highly efficient and widely used, but resistance is a major obstacle to successful therapy. Several underlying mechanisms have been proposed but were only reported for a minority of resistant patients. The proteasome is a large and complex machinery. Here, we focus on the AAA ATPases of the 19S proteasome regulator (PSMC1-6) and their implication in PI resistance. As an example of cancer evolution and the acquisition of resistance, we conducted an in-depth analysis of an index patient by applying FISH, WES, and immunoglobulin-rearrangement sequencing in serial samples, starting from MGUS to newly diagnosed Multiple Myeloma to a PI-resistant relapse. The WES analysis uncovered an acquired PSMC2 Y429S mutation at the relapse after intensive bortezomib-containing therapy, which was functionally confirmed to mediate PI resistance. A meta-analysis comprising 1499 newly diagnosed and 447 progressed patients revealed a total of 36 SNVs over all six PSMC genes that were structurally accumulated in regulatory sites for activity such as the ADP/ATP binding pocket. Other alterations impact the interaction between different PSMC subunits or the intrinsic conformation of an individual subunit, consequently affecting the folding and function of the complex. Interestingly, several mutations were clustered in the central channel of the ATPase ring, where the unfolded substrates enter the 20S core. Our results indicate that PSMC SNVs play a role in PI resistance in MM.

The study of cell-free DNA (cfDNA) and other peripheral blood components (known as “liquid biopsies”) is promising and has been investigated especially in solid tumors. Nevertheless, it is increasingly showing greater utility in the diagnosis, prognosis, and response to treatment of hematological malignancies; in the future, it could prevent invasive techniques, such as bone marrow (BM) biopsy. Most of the studies about this topic have been focused on B cell lymphoid malignancies; some of them have shown that cfDNA can be used as a novel way for diagnosis and minimal residual monitoring in B cell lymphomas, using techniques such as next-generation sequencing (NGS). In myelodysplastic syndromes, multiple myeloma, or chronic lymphocytic leukemia, liquid biopsies may allow for an interesting genomic representation of the tumor clones affecting different lesions (spatial heterogeneity). In acute leukemias, it can be helpful in the monitoring of early treatment response and the prediction of treatment failure. In chronic lymphocytic leukemia, the evaluation of cfDNA permits the definition of clonal evolution and drug resistance in real-time. However, there are limitations such as the difficulty in obtaining sufficient circulating tumor DNA for achieving a high sensitivity to assess minimal residual disease or the lack of standardization of the method and clinical studies to confirm its prognostic impact. This review focuses on clinical applications of cfDNA on minimal residual disease in hematological malignancies.

The study of cell-free DNA (cfDNA) and other peripheral blood components (known as “liquid biopsies”) is promising, and has been investigated especially in solid tumors. Nevertheless, it is increasingly showing a greater utility in the diagnosis, prognosis, and response to treatment of hematological malignancies; in the future, it could prevent invasive techniques, such as bone marrow (BM) biopsies. Most of the studies about this topic have focused on B-cell lymphoid malignancies; some of them have shown that cfDNA can be used as a novel way for the diagnosis and minimal residual monitoring of B-cell lymphomas, using techniques such as next-generation sequencing (NGS). In myelodysplastic syndromes, multiple myeloma, or chronic lymphocytic leukemia, liquid biopsies may allow for an interesting genomic representation of the tumor clones affecting different lesions (spatial heterogeneity). In acute leukemias, it can be helpful in the monitoring of the early treatment response and the prediction of treatment failure. In chronic lymphocytic leukemia, the evaluation of cfDNA permits the definition of clonal evolution and drug resistance in real time. However, there are limitations, such as the difficulty in obtaining sufficient circulating tumor DNA for achieving a high sensitivity to assess the minimal residual disease, or the lack of standardization of the method, and clinical studies, to confirm its prognostic impact. This review focuses on the clinical applications of cfDNA on the minimal residual disease in hematological malignancies.

Background: The impact of coronavirus disease 2019 (COVID-19) on hematological patients has not been comprehensively reported to date. Methods: We analyzed 39 hematological patients diagnosed with SARS-CoV-2 infection at our institution from March 7 to April 7, 2020. Clinical characteristics and outcomes were compared to a matched contemporary control group of 53 non-cancer patients hospitalized at our center. Univariate and multivariate analyses were carried out to assess the risk factors associated with poor outcome. Results: Median patient age was 64.7 years (range 36-88 years). The most frequent hematological diseases were lymphoma (30%), multiple myeloma (30%), and chronic lymphocytic leukemia (15%). On the WHO severity scale, 12.8% of the cancer patients were classified as mild, 41% as moderate, and 46.2% as severe. Most of the hematological patients were treated with hydroxychloroquine (89%) and lopinavir/ritonavir (79.5%); 51% of the patients received corticoids and 30.8% (n=12) received tocilizumab. In the multivariate analysis, we observed that only age >70 years and C reactive protein >10 mg/dl were associated with higher risk of death (odds ratio 34.86 (3.407-356.8) and 13.56 (1.28-143.45), respectively). An unfavorable impact of chemotherapy administration on COVID-19 outcome was not demonstrated. The non-hematological and hematological patients had similar clinical and laboratory characteristics; however, but mortality was higher in hematological patients (35.9% vs. 13.2%; Odds Ratio 6.5; 95% CI=1.868-23.688; P=0.003). Conclusion: Patients with hematological malignancies had a similar incidence of COVID-19, but the severity and mortality were much higher than in non-cancer patients even in the absence of therapy. Funding Statement: This work received funding from the research contract COV20/00181 from the Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III. Our research group was supported by the Fundacion Cris contra el cancer. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This retrospective study was approved by the Hospital Universitario 12 de Octubre Institutional Review Board (n 20/182).

INTRODUCTION Older AML patients have a different mutational landscape compared to younger patients. The prognostic classification of AML proposed by the European Leukemia Net (2017) is based on the presence of mutations in FLT3 (ITD), NPM1, CEBPA, RUNX1, ASXL1 and TP53. However, our group has identified a high-risk prognostic score in older patients with AML, who are undergoing treatment with azacitidine or low-dose cytarabine plus fludarabine, which predict a shorter survival. OBJECTIVE Validation of the previously identified high-risk prognostic score, defined by the presence of mutations in NRAS or TP53, in 3 cohorts of patients with AML who have been studied by NGS with a custom panel in the healthcare practice (Cohort 1: Intensive treatment; cohort 2: Hypomethylating agents and cohort 3: low-dose cytarabine) METHODS The study was conducted on a series of 535 patients diagnosed with AML (mean age 67). Patients evaluated for OS and RFS were 497 cases: intensive treatment (schemes 3+7 or similar; n=238), hypomethylating agents (azacitidine, decitabine; n=113) and treated with low-dose cytarabine (n=146). 38 patients on supportive therapy were excluded. Mutational profile was identified at diagnosis by NGS technique (Ion Torrent System), using a custom panel of 41 genes involved in myeloid pathologies: ASXL1, BCOR, BCORL1, CALR, CBL, CEBPA, DNMT3A, EPAS1, EPOR, ETV6, EZH2, FLT3, IDH1, IDH2, JAK2, KDM6A, KIT, KMT2A, KRAS, MPL, NF1, NPM1, NRAS, PHF6, PRPF40B, RAD21, RUNX1, SETBP1, SF3A1, SF3B1, SH2B3, SMC1A, SRSF2, STAG2, TET2, THPO, TP53, U2AF1, VHL, WT1 y ZRSR2. The mean OS and RFS were compared by means of Kaplan-Meier curves using the log-rank test. The bioinformatics analysis was performed with the SPSS software. RESULTS The median SG and RFS of this series was 10.8 months and 6.9 months respectively. The mutational profile in older patients was different from that analyzed in younger patients. We observed greater presence of mutations in NPM1 in younger patients (34.4 vs 18.6%, p=0.04), while in older than 65 years were identified more mutations in ASXL1 (3.9 vs 16.6%, p The median OS for intensively treated patients with a low-risk prognostic score was 49.1 months (17.56, 80.60) vs. 18.9 (14.98, 22.79) for high-risk patients (p=0.015). The median RFS was 45.2 months (5.2; 85.14) for low-risk patients vs. 42.1 (18.35; 65.92) for high-risk patients (p=0.167). The median OS for low-risk patients treated with hypomethylating agents was 13.2 months (9.02, 17.47) vs. 4.8 (1.6, 7.9) for patients with a high-risk score (p=0.002). The median RFS was 9.9 months (7.4, 12.3) for low-risk patients vs. 14.9 (10.1, 19.8) for high-risk patients (p=0.682). The median OS for patients treated with low-dose cytarabine was 8.4 months (4.9, 12.1) for low risk vs. 3.1 (1.22, 4.94) for high risk (p CONCLUSIONS We have confirm that exist differences in the mutational profile between older and younger AML patients and these differences have implications in the definition of risk of these patients. The prognostic score defined by the presence of mutations in the TP53 and NRAS genes, has been validated as an adverse prognostic factor across the three treatment groups studied (intensive treatment, hypomethylating agents and low-dose cytarabine) for OS, and this score no predict risk of relapse in the cohorts with intensive and hypomethylating treatments at difference to the low-dose cytarabine cohort. ML.M. enjoys a research grant from the Spanish Society of Hematology and Hemotherapy. This work has been financed thanks to the aid PI16/01225 and PI19/01518, from the Instituto de Salud Carlos III (Ministerio de Economía, Industria y Competitividad) and co-financed by the European Development Fund. Disclosures Montesinos: Astellas, Novartis, Janssen: Speakers Bureau; Celgene, Pfizer, Abbvie: Consultancy; Pfizer, Abbvie, Daiichi Sankyo: Research Funding. Martinez-Lopez:Incyte: Consultancy, Research Funding; Janssen: Consultancy, Honoraria; Janssen-cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; BMS: Consultancy, Research Funding. Sanz:Teva, Daiichi-Sankyo, Orsenix, AbbVie, Novartis, and Pfizer: Other: Consulting or Advisory Role.

Introduction: Myeloid malignancies are clonal disorders of hematopoietic stem cells and include acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) and myeloproliferative neoplasm (MPN). Common biological markers have been described in the molecular pathogenesis, including gene mutations in splicing factors, epigenetic modifiers, transcription factors, signal pathways and tumor suppressors. These mechanisms have been associated with MDS and MPN progression to AML. Objectives: The main objective of this study is to identify differences in the mutational landscape of myeloid malignancies and describe mutation frequencies of genes and functional pathways in each neoplasm, as well as determine their clinical impact. Methods: This study involved a retrospective analysis of 430 patients with AML (209), MDS (106) and Philadelphia negative MPN (86) diagnosed in the Hospital Universitario 12 de Octubre (Spain). They were analyzed by a next generation sequencing (NGS)- panel for myeloid malignancies. The panel include 32 genes: CALR, ASXL1, EZH2, PHF6, DNMT3A 2, TET2, IDH1, IDH2, KDM6A, KMT2A, SF1, SF3A1, SF3B1, SRSF2, U2AF1, ZRSR2, PRPF40B, EPOR, FLT3, JAK2, KIT, SH2B3, MPL, CBL, HRAS, NRAS, KRAS, ETV6, RUNX1, VHL, TP53, PTEN. In addition, there were included 29 patients diagnosed with benign pathology that were referred to rule out MPN or congenital polyglobulia. Results: In the analyzed cohort we obtained a larger number of mutations in the more aggressive malignancies, AML and MDS. Mutations in epigenetic modifiers and signal pathways were the most frequent detected (31% and 24% respectively). The epigenetic modifiers were notably affected in AML (78%) and MDS (60.4%), whereas signal pathways were mutated more frequently in MPN (70.9%). Transcription factors, tumor suppressors and splicing factors mutations were more detected in AML and MDS (40%, 32%, 44% and 22%, 13%, 32% respectively). The mutation landscape obtained by genes was: Signal pathways: FLT3, NRAS, KIT, KRAS y SH2B3 were specially detected in AML (25%, 11%, 6%, 5% and 4% respectively). JAK2, CALR and MPL in MPN (38%, 15% and 6% respectively). Transcription factors: RUNX1, ETV6, PHF6, CEBPA and WT1 mutations were regularly observed in AML (21%, 6%, 6%, 6% and 5% respectively), and GATA1 in SMD (3.8%). Tumor suppressors: TP53 was particularly affected in AML (21%) and MDS (11%). Epigenetic modifiers: TET2 was notably mutated in MDS (32%), whereas ASXL1, DNMT3A, IDH2, IDH1 and EZH2 were in AML (21%, 21%, 17% 16% and 8% respectively). Splicing factors: SF3B1 was more frequently detected in MDS (18%) than AML (7%), whereas ZRSR2 presented a similar frequency in both pathologies (around 8%). U2AF1 was most commonly mutated in MPN (9%). SRSF2 was specially mutated in AML (23%). SF3A1 was altered in around 1%, similar in all three malignancies. With regard to survival studies, the presence of mutations in splicing factors (primarily in U2AF1) and its absence in signal pathways conferred an adverse outcome for overall survival (OS) in MPN. In MDS, gene mutations in tumor suppressors (especially TP53), U2AF1 splicing factor and EZH2 epigenetic modifier were associated with poor outcome. In our series of AML, gene mutations in tumor suppressors and TP53 were related to unfavorable prognosis in OS. Conclusion: The largest number of mutations and affected genes observed in AML suggest that leukemic transformation of MDS and MPN is conditioned by acquisition of new mutations. We observed different frequencies of mutations between AML, MDS and MPN that could guide the diagnostic and identify new targets of treatment. Further, some mutations have demonstrated differential prognostic impact. An extension of this study and the design of an algorithm with mutation data to elucidate a more accurate molecular prognosis will be presented at the meeting. This work has been financed thanks to the grant PI16/01225, PI 19/01518 and PI19/00730 from the Instituto de Salud Carlos III (Ministerio de Economia, Industria y Competititvidad) and cofinanced by the European Development Fund. Figure 1. Mutations detected (%) in AML, MDS and MPN classified by function. Table 1. Median overall survival of patients with MPN, MDS and AML according to gene state (mutated or not). Figure Disclosures No relevant conflicts of interest to declare.

AIM To evaluate all the references about primary gallbladder hidatidosis looking for best treatment evidence. METHODS Search: 1966-2015 in MEDLINE, Cochrane Library, SciELO, and Tripdatabase. KEY WORDS "gallabladder hydatid disease" and "gallbladder hydatid cyst". We found 124 papers in our searches but only 14 papers including 16 cases were about hydatid cyst of the gallbladder (GBHC). RESULTS Eight cases of GBHC were women and seven men. One not mentioned. Median age was 48.3 years. The most frequent clinical symptom was abdominal pain (94%) usually in the right upper quadrant. Ultrasound was performed in ten patients (62.5%) but in most cases a combination of several techniques was performed. The location of the cysts was intravesicular in five patients. Five patients presented GBHC and liver hydatid cysts. Two patients presented cholelithiasis and one choledocholithiasis. The most frequent surgical technique was cholecystectomy by laparotomy (81.25%). Simultaneous surgery of liver cysts was carried out in five cases. Eleven patients did not present postoperative complications, but one died. The mean hospital stay was seven days. No recurrence of GBHC was recorded. CONCLUSION In GBHC, the most frequent symptom is right hypocondrium pain (evidence level V). Best diagnostic methods are ultrasound and computed tomography (level V, grade D). Suggested treatment is open cholecystectomy and postoperative albendazole (level V, grade D) obtaining good clinical results and none relapses.