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Dambach  Micha  Fieber  Jakob  Wanzenried  Manuel  Fehr  Tobias  Konrad  Christoph  Goertz  Roland  Fieber  David 《Der Anaesthesist》2022,71(11):846-851
Die Anaesthesiologie - Die Anwendung von hohen Sauerstoffkonzentration birgt Gefahren für Patienten und Anwender. Hohe Umgebungskonzentrationen an Sauerstoff bergen die Gefahr von...  相似文献   
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A positive relationship between treatment volume and outcome quality has been demonstrated in the literature and is thus evident for a variety of procedures. Consequently, policy makers have tried to translate this so-called volume–outcome relationship into minimum volume regulation (MVR) to increase the quality of care—yet with limited success. Until today, the effect of strict MVR application remains unclear as outcome quality gains cannot be estimated adequately and restrictions to application such as patient travel time and utilization of remaining hospital capacity are not considered sufficiently. Accordingly, when defining MVR, its effectiveness cannot be assessed. Thus, we developed a mixed integer programming model to define minimum volume thresholds balancing utility in terms of outcome quality gain and feasibility in terms of restricted patient travel time and utilization of hospital capacity. We applied our model to the German hospital sector and to four surgical procedures. Results showed that effective MVR needs a minimum volume threshold of 125 treatments for cholecystectomy, of 45 and 25 treatments for colon and rectum resection, respectively, of 32 treatments for radical prostatectomy and of 60 treatments for total knee arthroplasty. Depending on procedure type and incidence as well as the procedure’s complication rate, outcome quality gain ranged between 287 (radical prostatectomy) and 977 (colon resection) avoidable complications (11.7% and 11.9% of all complications). Ultimately, policy makers can use our model to leverage MVR’s intended benefit: concentrating treatment delivery to improve the quality of care.

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Purpose

Many authors suggest that extremity soft tissue sarcomas (ESTS) do not change significantly in size during preoperative radiation therapy (RT). This cone beam computed tomography study investigates the justification to deliver the entire course with 1 initial RT plan by observing anatomic changes during RT.

Methods and Materials

Between 2015 and 2017, 99 patients with ESTS were treated with either curative (n = 80) or palliative intent (n = 19) with a regimen of at least 6 fractions. The clinical target volume to planning target volume margin was 1 cm. Action levels were assigned by radiation technicians. An extremity contour change of >1 cm and/or tumor size change >0.5 cm required a physician's action before the next fraction.

Results

A total of 982 cone beam computed tomography logfiles were studied. In 41 of 99 patients, the dose coverage of the initial treatment plan was fully satisfactory throughout the RT course. However, action levels were observed in 58 patients (59%). In 41 of these 58 patients, a contour increase of 5 to 23 mm was noted (29 tumor size increase only, 3 extremity contour increase, and 9 both). In 21 of 58 patients, a decrease of 5 to 33 mm was observed (20 tumor size decrease only and 1 tumor size decrease and extremity contour decrease). In 4 cases, contours initially increased and subsequently decreased. In 33 of 41 patients with increasing contours, the dose distribution adequately covered gross tumor volume because of the 1 cm planning target volume margin applied. For the remaining 8 patients (8%), the plan needed to be adapted.

Conclusions

ESTS volumes may change substantially during RT in 59% of all patients, leading to plan adaptations resulting from increased volumes in 8%. Daily critical observation of these patients is mandatory to avoid geographic misses because of increases in size and overdosing of normal tissues when masses shrink.  相似文献   
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The efficacy of cancer vaccines has been limited by the immunosuppressive tumor microenvironment, which can be alleviated by immune checkpoint inhibitor (ICI) therapy. Here, we tested if oncolytic viruses (OVs), similar to ICI, can also synergize with cancer vaccines by modulating the tumor microenvironment. VSV-GP, a chimeric vesicular stomatitis virus (VSV) pseudotyped with the glycoprotein (GP) of the lymphocytic choriomeningitis virus, is a promising new OV candidate. Here, we show that in mouse B16-OVA melanoma, combination treatment of VSV-GP with an ovalbumin (OVA) peptide-loaded dendritic cell (DC) vaccine (DCVacc) significantly enhanced survival over the single agent therapies, although both DCVacc and DCVacc/VSV-GP treatments induced comparable levels of OVA-specific CD8 T cell responses. Virus replication was minimal so that direct viral oncolysis in B16-OVA did not contribute to this synergism. The strong therapeutic effect of the DCVacc/VSV-GP combination treatment was associated with high numbers of tumor-infiltrating, highly activated T cells and the relative reduction of regulatory T cells in treated and contra-lateral nontreated tumors. Accordingly, depletion of CD8 T cells but not natural killer cells abrogated the therapeutic effect of DCVacc/VSV-GP supporting the crucial role of CD8 T cells. In addition, a drastic increase in several proinflammatory cytokines was observed in VSV-GP-treated tumors. Taken together, OVs, similar to ICI, have the potential to markedly increase the efficacy of cancer vaccines by alleviating local immune suppression in the tumor microenvironment.  相似文献   
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Liver resection for colorectal liver metastases has emerged to highly successful treatment in the last decades. Key to this success is complete hepatic tumor removal and systemic disease control by chemotherapy. Associating liver partition and portal vein ligation for staged hepatectomy is the most recent two-stage resection strategy for patients with very small future liver remnant making complete tumor removal possible within 1 to 2 weeks. Oncological outcome data are being collected at the moment and first results from small series reveal promising results.  相似文献   
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BackgroundTreatment decisions in routine clinical practice are based on reports of clinical trials, which represent highly selected populations. Limited studies reported real-world evidences representing routine clinical practices in patients with renal-cell carcinoma (RCC) in Europe. The aim of this retrospective, noninterventional chart review was to collect data on the treatment landscape for patients with advanced/metastatic RCC in routine clinical practice in a broader patient population in Austria.Patients and MethodsPatients with advanced/metastatic RCC receiving systemic treatment between June 2010 and June 2016 across 12 centers in Austria were included. Parameters were entered into an electronic case report form from the participating sites via the application Hermesoft electronic data capture system. Progression-free survival (PFS) and overall survival (OS) were the 2 primary end points.ResultsThe median PFS and OS were 12 months and 44 months, respectively (first-line PFS was 14 months for pazopanib and 13 months for sunitinib; first-line OS was 44 months for pazopanib and 48 months for sunitinib). Factors influencing the OS were sex, with female patients at a significantly higher risk than male patients (hazard ratio = 1.719), Eastern Cooperative Oncology Group performance status > 0 increased the risk twice (hazard ratio = 2.048), and number of metastases > 3 before the first line doubled the risk compared to metastases (hazard ratio = 2.064).ConclusionOS in this retrospective chart review was considerably longer than the previous reports in real-world patients, underlining the benefit of current RCC treatment options in routine clinical practice.  相似文献   
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Journal of Neuro-Oncology - Gliomatosis cerebri (GC) is a rare growth pattern of glioblastoma whose diffuse nature is reflected by unspecific, relatively uniform findings on conventional MRI. In...  相似文献   
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