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61.
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Optimal selection of optimization bolus thickness in planning of VMAT breast radiotherapy treatments
《Medical Dosimetry》2019,44(3):266-273
The aim of this study was to find an optimal optimization skin flash thickness in volumetric modulated arc radiotherapy of the breast in consideration of soft tissue deformations during the treatment course. Ten breast radiotherapy patients with axillary lymph node inclusion were retrospectively planned with volumetric modulated arc radiotherapy technique. The plans were optimized with the planning target volume (PTV) extending outside the skin contour by 0, 5, 7, and 10 mm; and with optimization boluses of 3 or 5 mm on the extended PTV. The final dose was calculated without the bolus. The plans were compared in terms of PTV homogeneity and conformity, and dose minima and maxima. The doses to organs at risk were also evaluated. The doses were recalculated in real patient geometries based on cone beam computed tomography (CBCT) images captured 3 to 6 times during each patient's treatment course. The optimization to the PTV without the PTV extension resulted in the best CTV coverage in the original plans (V95% = 98.0% ± 1.2%). However, when these plans were studied in real CBCT-based patient geometries, the CTV V95% was compromised (94.6% ± 8.3%). In addition, for the surface (4 mm slap inside the PTV 4 mm below the body contour) dose V95% was reduced from the planned 74.7% ± 7.5% to the recalculated 65.5% ± 11.5%. Optimization with an 8-mm bolus to a PTV with 5-mm extension was the most robust choice to ensure the CTV and surface dose coverage (recalculated V95% was 95.2% ± 6.4% and 74.6% ± 8.4%, respectively). In cases with the largest observed deformations, even a 10-mm PTV extension did not suffice to cover the target. Optimization with a 5-mm PTV extension and an 8-mm optimization bolus improved the surface dose and slightly improved the CTV dose when compared to no extension plans. For deformations over 1 cm, no benefit was seen in PTV extensions and replanning is recommended. Frequent tangential and CBCT imaging should be used during treatment course to detect potential large anatomical changes. 相似文献
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《European journal of surgical oncology》2019,45(6):931-940
BackgroundIsolated local recurrent or persistent esophageal cancer (EC) after curative intended definitive (dCRT) or neoadjuvant chemoradiotherapy (nCRT) with initially omitted surgery, is a potential indication for salvage surgery. We aimed to evaluate safety and efficacy of salvage surgery in these patients.Material and methodsA systematic literature search following PRISMA guidelines was performed using databases of PubMed/Medline. All included studies were performed in patients with persistent or recurrent EC after initial treatment with dCRT or nCRT, between 2007 and 2017. Survival analysis was performed with an inverse-variance weighting method.ResultsOf the 278 identified studies, 28 were eligible, including a total of 1076 patients. Postoperative complications after salvage esophagectomy were significantly more common among patients with isolated persistent than in those with locoregional recurrent EC, including respiratory (36.6% versus 22.7%; difference in proportion 10.9 with 95% confidence interval (CI) [3.1; 18.7]) and cardiovascular complications (10.4% versus 4.5%; difference in proportion 5.9 with 95% CI [1.5; 10.2]). The pooled estimated 30- and 90-day mortality was 2.6% [1.6; 3.6] and 8.0% [6.3; 9.8], respectively. The pooled estimated 3-year and 5-year overall survival (OS) were 39.0% (95% CI: [35.8; 42.2]) and 19.4% [95% CI:16.5; 22.4], respectively. Patients with isolated persistent or recurrent EC after initial CRT had similar 5-year OS (14.0% versus 19.7%, difference in proportion −5.7, 95% CI [-13.7; 2.3]).ConclusionsSalvage surgery is a potentially curative procedure in patients with locally recurrent or persistent esophageal cancer and can be performed safely after definitive or neoadjuvant chemoradiotherapy when surgery was initially omitted. 相似文献
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IntroductionWith the increasing reliance on targeted therapies and immunotherapy, no standard management strategy is today available for the treatment of locally, distant, or both renal cell carcinoma (RCC) recurrences, and their surgical treatment seems to play a crucial role. We report the 20-year experience of our center evaluating the short- and long-term outcomes of patients undergone surgical resection of RCC recurrences, and the possible role of repeated surgical resections of RCC recurrences.Materials and methodsFrom January 1999 to January 2019, 40 patients underwent surgical resection of isolated locally recurrent RCC (iLR-RCC-group), locally recurrent RCC associated with the presence of distant recurrence (LR-DR-RCC-group), and distant-only recurrent RCC (DR-RCC-group). Data regarding pre-, intra-, post-operative course, and follow-up, prospectively collected in an institutional database, were retrospectively analyzed and compared.ResultsiLR-RCC-group was composed of 9 patients, LR-DR-RCC-group of 6 patients, and DR-RCC-group of 25 patients. The recurrence rate was 55.6% (5/9 patients) in iLR-RCC-group, 50% (3/6 patients) in LR-DR-RCC-group, and 44% (11/25) patients in DR-RCC-group, p = 0.830. 3/5 (60%) patients in iLR-RCC-group, 2/3 (66.7%) patients in LR-DR-RCC-group, and 7/11 (63.6%) patients in DR-RCC group underwent to almost one further local treatments of their recurrences, respectively (p = 0.981). No differences in the mean disease-free survival (p = 0.384), overall survival (OS) (p = 0.881), and cancer-specific survival (p = 0.265) were reported between the three groups. In DR-RCC-group, patients who underwent further local treatments of new recurrences presented a longer OS: 150.7 versus 66.5 months (p = 0.004).ConclusionsA surgical resection of RCC recurrences should be always taken in consideration, also in metastatic patients and/or in those who have already undergone surgery of previous RCC recurrence, whenever radicality is still possible, because this approach may offer a potentially long survival. 相似文献
66.
《Journal of vascular and interventional radiology : JVIR》2020,31(2):286-293
PurposeTo evaluate tumor and ablation zone morphology and densitometry related to tumor recurrence in participants with Stage IA non–small cell lung cancer undergoing radiofrequency ablation in a prospective, multicenter trial.Materials and MethodsForty-five participants (median 76 years old; 25 women; 20 men) from 16 sites were followed for 2 years (December 2006 to November 2010) with computed tomography (CT) densitometry. Imaging findings before and after ablation were recorded, including maximum CT attenuation (in Hounsfield units) at precontrast and 45-, 90-, 180-, and 300-s postcontrast.ResultsEvery 1-cm increase in the largest axial diameter of the ablation zone at 3-months’ follow-up compared to the index tumor reduced the odds of 2-year recurrence by 52% (P = .02). A 1-cm difference performed the best (sensitivity, 0.56; specificity, 0.93; positive likelihood ratio of 8). CT densitometry precontrast and at 45 seconds showed significantly different enhancement patterns in a comparison among pretreated lung cancer (delta = +61.2 HU), tumor recurrence (delta = +57 HU), and treated tumor/ablation zone (delta [change in attenuation] = +16.9 HU), (P < .0001). Densitometry from 45 to 300 s was also different among pretreated tumor (delta = −6.8 HU), recurrence (delta = −11.2 HU), and treated tumor (delta = +12.1 HU; P = .01). Untreated and residual tumor demonstrated washout, whereas treated tumor demonstrated increased attenuation.ConclusionsAn ablation zone ≥1 cm larger than the initial tumor, based on 3-month follow-up imaging, is recommended to decrease odds of recurrence. CT densitometry can delineate tumor versus treatment zones. 相似文献
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《Gaceta sanitaria / S.E.S.P.A.S》2016,30(5):389-392
Life expectancy for people with severe mental disorders is up to 25 years less in comparison to the general population, mainly due to diseases caused or worsened by smoking. However, smoking is usually a neglected issue in mental healthcare settings. The aim of this article is to describe a strategy to improve tobacco control in the hospital mental healthcare services of Catalonia (Spain). To bridge this gap, the Catalan Network of Smoke-free Hospitals launched a nationwide bottom-up strategy in Catalonia in 2007. The strategy relied on the creation of a working group of key professionals from various hospitals —the early adopters— based on Rogers’ theory of the Diffusion of Innovations. In 2016, the working group is composed of professionals from 17 hospitals (70.8% of all hospitals in the region with mental health inpatient units). Since 2007, tobacco control has improved in different areas such as increasing mental health professionals’ awareness of smoking, training professionals on smoking cessation interventions and achieving good compliance with the national smoking ban. The working group has produced and disseminated various materials, including clinical practice and best practice guidelines, implemented smoking cessation programmes and organised seminars and training sessions on smoking cessation measures in patients with mental illnesses. The next challenge is to ensure effective follow-up for smoking cessation after discharge. While some areas of tobacco control within these services still require significant improvement, the aforementioned initiative promotes successful tobacco control in these settings. 相似文献
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《The spine journal》2020,20(10):1602-1609
BACKGROUNDSurgical site infections are a major driver of morbidity and increased costs in the postoperative period after spine surgery. Current tools for surveillance of these adverse events rely on prospective clinical tracking, manual retrospective chart review, or administrative procedural and diagnosis codes.PURPOSEThe purpose of this study was to develop natural language processing (NLP) algorithms for automated reporting of postoperative wound infection requiring reoperation after lumbar discectomy.PATIENT SAMPLEAdult patients undergoing discectomy at two academic and three community medical centers between January 1, 2000 and July 31, 2019 for lumbar disc herniation.OUTCOME MEASURESReoperation for wound infection within 90 days after surgeryMETHODSFree-text notes of patients who underwent surgery from January 1, 2000 to December 31, 2015 were used for algorithm training. Free-text notes of patients who underwent surgery after January 1, 2016 were used for algorithm testing. Manual chart review was used to label which patients had reoperation for wound infection. An extreme gradient-boosting NLP algorithm was developed to detect reoperation for postoperative wound infection.RESULTSOverall, 5,860 patients were included in this study and 62 (1.1%) had a reoperation for wound infection. In patients who underwent surgery after January 1, 2016 (n=1,377), the NLP algorithm detected 15 of the 16 patients (sensitivity=0.94) who had reoperation for infection. In comparison, current procedural terminology and international classification of disease codes detected 12 of these 16 patients (sensitivity=0.75). At a threshold of 0.05, the NLP algorithm had positive predictive value of 0.83 and F1-score of 0.88.CONCLUSIONTemporal validation of the algorithm developed in this study demonstrates a proof-of-concept application of NLP for automated reporting of adverse events after spine surgery. Adapting this methodology for other procedures and outcomes in spine and orthopedics has the potential to dramatically improve and automatize quality and safety reporting. 相似文献