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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und...  相似文献   
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Die Onkologie - Das Urothelkarzinom (UC) der Blase gilt als chemotherapiesensibler Tumor. Dennoch liegt die Fünfjahresüberlebensrate im Stadium IV?<?5?%....  相似文献   
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European Surgery - The beneficial outcomes of hepatectomy in patients with colorectal metastases have encouraged the attempts of repeated hepatectomy in patients with recurrent disease. Although...  相似文献   
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Background

There is evidence linking metformin to improved prostate cancer–related outcomes.

Patients and Methods

Twenty-five men with metastatic castration-resistant prostate cancer and prostate-specific antigen (PSA) progression while receiving treatment with abiraterone from 3 Swiss centers were included in this single-arm phase 2 trial between November 2013 and September 2016. Metformin was added to abiraterone continuously at 1000 mg twice daily in uninterrupted 4-week cycles. The primary end point was the absence of disease progression at 12 weeks (PFS12). The Fleming single-stage design was applied. With a 5% significance level and 80% power, 25 patients were required to test PFS12 ≤ 15% (H0) compared to ≥ 35% (H1). Secondary end points included toxicity and safety issues. The study was registered at ClinicalTrials.gov (NCT01677897).

Results

The primary end point PFS12 was 12% (3 of 25 patients) (95% confidence interval, 3-31). Most patients had PSA progression, almost half had radiographic progression, but only 1 patient had symptomatic progression. Eleven (44%) of 25 patients had grade 1 and 2 patients each grade 2 (8%) or grade 3 (8%) gastrointestinal toxicity (nausea, diarrhea, loss of appetite). One patient discontinued treatment at week 5 because of intolerable grade 3 diarrhea.

Conclusion

The addition of metformin to abiraterone for patients with metastatic castration-resistant prostate cancer and PSA progression while receiving abiraterone therapy does not affect further progression and has no meaningful clinical benefit. A higher-than-expected gastrointestinal toxicity attributed to metformin was observed.  相似文献   
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Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980–2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28–1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92–1.39) and 1.55 (95% CI 1.04–2.31) 10–14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83–1.52; HR 1.08, 95% CI 0.79–1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker.  相似文献   
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Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis.  相似文献   
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