21 research outputs found

    Water Availability Is the Main Climate Driver of Neotropical Tree Growth

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    ‱ Climate models for the coming century predict rainfall reduction in the Amazonian region, including change in water availability for tropical rainforests. Here, we test the extent to which climate variables related to water regime, temperature and irradiance shape the growth trajectories of neotropical trees. ‱ We developed a diameter growth model explicitly designed to work with asynchronous climate and growth data. Growth trajectories of 205 individual trees from 54 neotropical species censused every 2 months over a 4-year period were used to rank 9 climate variables and find the best predictive model. ‱ About 9% of the individual variation in tree growth was imputable to the seasonal variation of climate. Relative extractable water was the main predictor and alone explained more than 60% of the climate effect on tree growth, i.e. 5.4% of the individual variation in tree growth. Furthermore, the global annual tree growth was more dependent on the diameter increment at the onset of the rain season than on the duration of dry season. ‱ The best predictive model included 3 climate variables: relative extractable water, minimum temperature and irradiance. The root mean squared error of prediction (0.035 mm.d–1) was slightly above the mean value of the growth (0.026 mm.d–1). ‱ Amongst climate variables, we highlight the predominant role of water availability in determining seasonal variation in tree growth of neotropical forest trees and the need to include these relationships in forest simulators to test, in silico, the impact of different climate scenarios on the future dynamics of the rainforest

    Efficacy, Safety and Cost of Regorafenib in Patients with Metastatic Colorectal Cancer in French Clinical Practice

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    Background Regorafenib is an orally administered multikinase inhibitor that has been approved for patients with chemotherapy-refractory metastatic colorectal cancer (mCRC). Even though regorafenib significantly improved survival in two international phase 3 trials (CORRECT and CONCUR), a high rate of treatment-related toxic effects and dose modifications were observed with a modest benefit. The aim of this study was to provide information concerning the efficacy, safety, and cost of regorafenib in patients with mCRC in clinical practice. Material and Methods We retrospectively reviewed patients treated with regorafenib monotherapy for unresectable mCRC in five Franche-ComtĂ© cancer hospitals (France). The primary end point was overall survival. Secondary end points were safety and descriptive cost analyses of patients treated with regorafenib in clinical practice. Another aim of this study was to assess the impact of regorafenib prescription on the risk of hospitalization in real-life practice. Results From January 2014 to August 2014, 29 consecutive patients were enrolled. Patients were heavily pretreated and were refractory to standard chemotherapies. The primary tumor sites were the colon and the rectum for 55% and 45% of patients, respectively. Fifteen patients (51%) harbored an RAS mutation. Eastern Cooperative Oncology Group - Performance Status (PS) was 0–1 for 86% of patients and 2 for 14% of patients. Nineteen patients (66%) initially received reduced doses of 120 or 80 mg/day. The median duration of treatment was 2.5 months (range, 0.13–11.4 months). Treatment-related adverse events occurred in 86% of patients. The most frequent adverse events of any grade were fatigue (35%), diarrhea (20%), and hand-foot skin reaction (20%). Grade 3 or 4 treatment-related adverse events occurred in 10 patients (35%). Three patients (10%) were admitted to hospital due to drug-related severe adverse events. The mean cost of patient management with regorafenib for the duration of treatment was 9908 ± 8191€, and median cost was 7917€ (Interquartile range (IQR) 4469-13,042). The median overall survival was six months (95% confidence interval, five to eight months). Conclusions The safety and efficacy of regorafenib in heavily pretreated mCRC patients was comparable, in our study, to prospective and retrospective trials. Toxic effects were mostly manageable in an outpatient setting. Regorafenib itself represented the most important (93%) part of supported costs. Even though most side effects were manageable in an outpatient setting, severe adverse events occurred from hospitalization in 10% of patients. These data should be confirmed in a larger real-life-based cohort. Identification of predictive biomarkers is needed for mCRC patient selection for regorafenib treatment

    Safety profile of new anticancer drugs.

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    International audienceImportance of the field: The development of targeted anticancer therapies stems from advances in molecular biology. New agents range from antibodies that form complexes with antigens on the surface of the cancer cell to small molecules that have been engineered to block key enzymatic reactions. The interaction of the antibody or drug with its target inhibits key pathways involved in cell proliferation or metastasis, or activates pathways leading to cell death. Such pathways constitute ideal pharmacological targets. Clinical benefits from these novel therapeutic strategies are striking for patients with metastatic diseases. Areas covered: This review analyses the main toxicities among most common targeted therapies that have been approved by the FDA or European Medicines Agency for their clinical utilisation in solid tumours treatment. What the reader will gain: Here, the main toxicity and safety data among new anticancer targeted therapies are described. Data are organised through the pathways targeted by the drugs. Take home message: The emergence of new targeted anticancer therapies promises more efficient and less toxic therapies. Generally, they are well tolerated, toxicities are commonly mild to moderate and can be handled rapidly. However, if most of these adverse events are manageable, life threatening and fatal complications can still occur

    Detection of neovessels in atherosclerotic plaques of rabbits using dynamic contrast enhanced MRI and 18F-FDG PET.

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    International audienceOBJECTIVE: The association of inflammatory cells and neovessels in atherosclerosis is considered a histological hallmark of high-risk active lesions. Therefore, the development and validation of noninvasive imaging techniques that allow for the detection of inflammation and neoangiogenesis in atherosclerosis would be of major clinical interest. Our aim was to test 2 techniques, black blood dynamic contrast enhanced MRI (DCE-MRI) and 18-fluorine-fluorodeoxyglucose (18F-FDG) PET, to quantify inflammation expressed as plaque neovessels content in a rabbit model of atherosclerosis. METHODS AND RESULTS: Atherosclerotic plaques were induced in the aorta of 10 rabbits by a combination of 2 endothelial abrasions and 4 months hyperlipidemic diet. Six rabbits underwent MRI during the injection of Gd-DTPA, whereas 4 rabbits were imaged after injection of 18F-FDG with PET. We found a positive correlation between neovessels count in atherosclerotic plaques and (1) Gd-DTPA uptake parameters evaluated by DCE-MRI (r=0.89, P=0.016) and (2) 18F-FDG uptake evaluated by PET (r=0.5, P=0.103 after clustered robust, Huber-White, standard errors analysis). CONCLUSIONS: DCE-MRI and 18F-FDG PET may allow for the evaluation of inflammation in atherosclerotic plaques of rabbits. These noninvasive imaging modalities could be proposed as clinical tools in the evaluation of lesion prognosis and monitoring of anti-angiogenic therapies

    Open-label, randomized multicentre phase II study to assess the efficacy and tolerability of sunitinib by dose administration regimen (dose modification or dose interruptions) in patients with advanced or metastatic renal cell carcinoma: study protocol of the SURF trial

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    Abstract Background Sunitinib is a tyrosine kinase inhibitor approved in the first-line metastatic renal cell carcinoma (MRCC) setting at the dose of 50 mg daily for 4 weeks followed by a pause of 2 weeks. Due to toxicity, this standard schedule (50 mg daily 4/2) can induce up to 50% of sunitinib dose modification (reduction and/or interruption). The current recommendation in such case is to reduce the dose to 37.5 mg per day (standard schedule 4/2). Recent data highlight an alternative schedule: 2 weeks of treatment followed by 1 week of pause (experimental schedule 2/1). The SURF trial is set up to evaluate prospectively experimental schedule 2/1 when toxicity occurs. This article displays the key elements of the study protocol. Methods/design SURF [NCT02689167] is a prospective, randomized, open-label phase IIb study. Patients are included at sunitinib initiation while receiving standard schedule 4/2 (50 mg daily) according to the marketing authorization indication. When a dose adjustment of sunitinib is required, patients are randomized between standard schedule 4/2 (37.5 mg daily) and experimental schedule 2/1 (50 mg daily). Key eligibility criteria are the following: patients with locally advanced inoperable or MRCC who are starting first-line treatment with sunitinib, with histologically or cytologically confirmed renal cancer clear cell variant or with a clear cell component, and with Karnofsky performance status ≄70%. The primary objective is to assess the median duration of sunitinib treatment (DOT) in each group. The key secondary objectives are progression-free survival, overall survival, time to randomization, objective response rate, safety, sunitinib dose intensity, health-related quality of life, and the description of main drivers triggering randomization. We hypothesized that experimental schedule 2/1 would result in an improvement in median DOT from 6 to 8.5 months. It was estimated that 112 patients would be needed in each arm during 24 months. In order to take into account the possibility of treatment discontinuation before randomization, 248 patients are necessary. Discussion The SURF trial is asking a pragmatic question adapted to the current practice on what is the best way to adapt sunitinib when treatment-related adverse events occur. The results of the SURF trial will bring high-value data to support the use of an alternative schedule in sunitinib treatment. Trial registration ClinicalTrials.gov, NCT02689167. Registered on 26 February 2016

    Génotypage moléculaire dans les cancers réfractaires de la thyroïde en 2021 : quand, comment, et pourquoi ? Un travail du réseau TUTHYREF

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    International audienceRefractory thyroid cancers include radio-iodine-refractory cancers, metastatic or locally advanced unresectable medullary and anaplastic thyroid cancers. Their management has been based for several years on the use of multi-target kinase inhibitors, with anti-angiogenic action, with the exception of anaplastic cancers usually treated with chemo- and radiotherapy. The situation has recently evolved due to the availability of molecular genotyping techniques allowing the discovery of rare but targetable molecular abnormalities. New treatment options have become available, more effective and less toxic than the previously available multi-target kinase inhibitors. The management of refractory thyroid cancers is therefore becoming more complex both at a diagnosis level with the need to know when, how and why to look for these molecular abnormalities but also at a therapeutic level, innovative treatments being hardly accessible. The cost of molecular analyzes and the access to treatments need also to be homogenized because disparities could lead to inequality of care at a national or international level. Finally, the strategy of identifying molecular alterations and treating these rare tumors reinforces the importance of a discussion in a multidisciplinary consultation meeting.Les cancers thyroĂŻdiens rĂ©fractaires regroupent les cancers de souche folliculaire rĂ©fractaires Ă  l’iode, les cancers mĂ©dullaires mĂ©tastatiques ou localement avancĂ©s non rĂ©sĂ©cables et les cancers anaplasiques. Leur prise en charge est basĂ©e depuis quelques annĂ©es sur l’utilisation d’inhibiteurs de kinase multicibles, Ă  action principalement anti-angiogĂ©nique, exception faite des cancers anaplasiques habituellement traitĂ©s par chimio- et radiothĂ©rapie. La situation a rĂ©cemment Ă©voluĂ© en raison de la mise Ă  disposition de techniques de gĂ©notypage molĂ©culaire permettant la dĂ©couverte d’anomalies molĂ©culaires rares mais ciblables, et de nouveaux traitements, possiblement plus efficaces et moins toxiques que les inhibiteurs de kinase multicibles prĂ©alablement disponibles. La prise en charge de ces cancers se complexifie donc Ă  la fois au niveau diagnostique avec la nĂ©cessitĂ© de savoir quand, comment et pourquoi rechercher ces anomalies molĂ©culaires mais Ă©galement au niveau thĂ©rapeutique, avec la question de la disponibilitĂ© des traitements innovants et de l’accĂšs aux essais cliniques. Le coĂ»t des analyses molĂ©culaires et l’accĂšs aux mĂ©dicaments sont Ă  harmoniser car des disparitĂ©s pourraient conduire Ă  une inĂ©galitĂ© des soins au niveau national ou international. Enfin, la stratĂ©gie d’identification des altĂ©rations molĂ©culaires et de traitement pour ces tumeurs rares renforce l’importance d’une discussion en rĂ©union de concertation pluridisciplinaire
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