Base-Position Error Rate Analysis of Next-Generation Sequencing Applied to Circulating Tumor DNA in Non-Small Cell Lung Cancer: A Prospective Study.

BACKGROUND: Circulating tumor DNA (ctDNA) is an approved noninvasive biomarker to test for the presence of EGFR mutations at diagnosis or recurrence of lung cancer. However, studies evaluating ctDNA as a noninvasive "real-time" biomarker to provide prognostic and predictive information in treatment monitoring have given inconsistent results, mainly due to methodological differences. We have recently validated a next-generation sequencing (NGS) approach to detect ctDNA. Using this new approach, we evaluated the clinical usefulness of ctDNA monitoring in a prospective observational series of patients with non-small cell lung cancer (NSCLC). METHODS AND FINDINGS: We recruited 124 patients with newly diagnosed advanced NSCLC for ctDNA monitoring. The primary objective was to analyze the prognostic value of baseline ctDNA on overall survival. ctDNA was assessed by ultra-deep targeted NGS using our dedicated variant caller algorithm. Common mutations were validated by digital PCR. Out of the 109 patients with at least one follow-up marker mutation, plasma samples were contributive at baseline (n = 105), at first evaluation (n = 85), and at tumor progression (n = 66). We found that the presence of ctDNA at baseline was an independent marker of poor prognosis, with a median overall survival of 13.6 versus 21.5 mo (adjusted hazard ratio [HR] 1.82, 95% CI 1.01-3.55, p = 0.045) and a median progression-free survival of 4.9 versus 10.4 mo (adjusted HR 2.14, 95% CI 1.30-3.67, p = 0.002). It was also related to the presence of bone and liver metastasis. At first evaluation (E1) after treatment initiation, residual ctDNA was an early predictor of treatment benefit as judged by best radiological response and progression-free survival. Finally, negative ctDNA at E1 was associated with overall survival independently of Response Evaluation Criteria in Solid Tumors (RECIST) (HR 3.27, 95% CI 1.66-6.40, p < 0.001). Study population heterogeneity, over-representation of EGFR-mutated patients, and heterogeneous treatment types might limit the conclusions of this study, which require future validation in independent populations. CONCLUSIONS: In this study of patients with newly diagnosed NSCLC, we found that ctDNA detection using targeted NGS was associated with poor prognosis. The heterogeneity of lung cancer molecular alterations, particularly at time of progression, impairs the ability of individual gene testing to accurately detect ctDNA in unselected patients. Further investigations are needed to evaluate the clinical impact of earlier evaluation times at 1 or 2 wk. Supporting clinical decisions, such as early treatment switching based on ctDNA positivity at first evaluation, will require dedicated interventional studies.

Hemoglobin determination with point-of-care testing, performance evaluation compared to central laboratory analyzers in transfusion decision, an in vitro and retrospective study.

INTRODUCTION: Point of care (POC) analyzers are an integral part of the patient care. Transfuse can be an emergency decision, not being a benign act, it is necessary to ensure that the hemoglobin value measured by the POC are comparable with the reference analyzer. The objective is to compare the analytical performance of three POCs: ABL800 Flex, Hemocue and iSTAT and a central laboratory analyzer: XN-10 and the impact on the transfusion decision. METHODS: An in vitro study was performed in 50 patients for whom a hemogram had been prescribed on the XN-10, the hemoglobin determination was performed in parallel on the three POCs. Then, retrospective study was performed to compare the hemoglobin values returned for matched samples in routine practice, 5505 for ABL800 Flex, 55 for Hemocue and 70 for iSTAT were analyzed. RESULTS: In vitro study shows systematic biases in the measurement of hemoglobin between the different analyzers, overestimation for the ABL800 Flex and the Hemocue, underestimation for the iSTAT. These biases are accentuated in current practice for iSTAT but decreased for ABL800 Flex. In the transfusion decision range from 70 to 100 g/L, there were 8.6% of clinically discordant results between the reference method and ABL, 34.8% for Hemocue and 21.4% for iSTAT. CONCLUSION: In addition to systematic biases, many additional factors may be involved for variation in hemoglobin measurement with POC. Thus, in the case of urgent transfusion decisions, sending a hemogram on a central laboratory analyzer seems to be essential, while being compatible with a life-threatening emergency.

Perls' Stain Guidelines from the French-Speaking Cellular Hematology Group (GFHC).

In order to standardize cellular hematology practices, the French-speaking Cellular Hematology Group (Groupe Francophone d'Hématologie Cellulaire, GFHC) focused on Perls' stain. A national survey was carried out, leading to the proposal of recommendations on insoluble iron detection and quantification in bone marrow. The criteria presented here met with a "strong professional agreement" and follow the suggestions of the World Health Organization's classification of hematological malignancies.

Chronic T cell receptor stimulation unmasks NK receptor signaling in peripheral T cell lymphomas via epigenetic reprogramming.

Peripheral T cell lymphomas (PTCLs) represent a significant unmet medical need with dismal clinical outcomes. The T cell receptor (TCR) is emerging as a key driver of T lymphocyte transformation. However, the role of chronic TCR activation in lymphomagenesis and in lymphoma cell survival is still poorly understood. Using a mouse model, we report that chronic TCR stimulation drove T cell lymphomagenesis, whereas TCR signaling did not contribute to PTCL survival. The combination of kinome, transcriptome, and epigenome analyses of mouse PTCLs revealed a NK cell-like reprogramming of PTCL cells with expression of NK receptors (NKRs) and downstream signaling molecules such as Tyrobp and SYK. Activating NKRs were functional in PTCLs and dependent on SYK activity. In vivo blockade of NKR signaling prolonged mouse survival, demonstrating the addiction of PTCLs to NKRs and downstream SYK/mTOR activity for their survival. We studied a large collection of human primary samples and identified several PTCLs recapitulating the phenotype described in this model by their expression of SYK and the NKR, suggesting a similar mechanism of lymphomagenesis and establishing a rationale for clinical studies targeting such molecules.

Crossover trial of an audience response system application for smartphone in undergraduate medical students.

This article was migrated. The article was marked as recommended. Objectives: Audience response systems (ARS) using dedicated devices have been shown to enhance interactivity, leading to an increase in knowledge acquisition. ARS applications for smartphones are easier to use, but the benefits of these applications might be negated by deleterious effects of smartphone usage on concentration. We investigated whether an ARS smartphone application (Socrative TM) is feasible and increases student satisfaction and knowledge acquisition. Methods: We performed a crossover study in the setting of a hematology course for second-year medical students. Two hundred and forty nine students were included in the study and analyzed for their access to the ARS application through a smartphone. The same interactive lectures were proposed by the same teachers. The first group (n=119) was asked to answer questions with the ARS application during the first 3 lectures, and without the application during the last 3 lectures; and conversely for the second group (n=130). The analysis of the final results was restricted to 146 students having attended to at least 5 of the 6 lectures and having a smartphone enabling the use of the ARS application. Student opinion was measured through questions based on a Likert scale, and knowledge acquisition was measured at short and long-term through multiple choice questions assessing either the first three lectures or the last three lectures. Results: Most of the students (86%) had a smartphone enabling the use of the application. They were satisfied by the use of the application (93%), and found that it increased both interactivity (92%) and concentration (68%). There was no difference in knowledge scores at short or long term. Conclusion: The use of an ARS application for smartphone is feasible and increases the satisfaction of the students, their concentration and the interactivity of the lectures. However, this does not translate into a measurable increase in knowledge acquisition.