823 research outputs found
La evidencia del cribado del cáncer de mama: la historia continúa
ResumenLa publicación de la nueva revisión Cochrane sobre el cribado de cáncer de mama mediante mamografía ha iniciado un nuevo período de discusión y reflexión sobre este cribado. Los autores de dicha revisión se han reafirmado en la falta de eficacia del cribado mamográfico, mientras que la actualización de la revisión de los estudios suecos y dos nuevas revisiones sistemáticas realizadas por la Agency for Healthcare Research and Quality para la US Preventive Services Task Force y por un grupo de trabajo bajo los auspicios de la IARC, que han tenido muy en cuenta las discusiones sobre los aspectos metodológicos de los ensayos discutidos en los últimos años, se han reafirmado en la eficacia del cribado mamográfico. No obstante, sigue abierto el debate sobre la efectividad y las recomendaciones en mujeres menores de 50 años. El debate actual ha puesto sobre la mesa aspectos como la mejor medida de los beneficios de un ensayo sobre cribado o los potenciales efectos adversos del cribado en forma de sobrediagnóstico o sus repercusiones sobre el tratamiento, que se discuten en este artículo. Asimismo, nos reafirma en la necesidad de introducir cribados de beneficio demostrado y discutir e informar a la población sobre estos beneficios, pero también sobre los riesgos y las incertidumbres del cribado del cáncer.AbstractThe publication of the new Cochrane review on screening for breast cancer with mamography has revived the debate on breats screening and raised some new topics. Whereas the Cochrane reviewers reasserted on their previous conclusion of the lack of efficacy of breast screening, the new review of the Swedish studies, the new systematic review of the Agency for Healthcare Research and Quality commissioned by the US Preventive Services Task Force, and the recent review of an IARC working group supported the efficacy of breast screening after carefully considering the methodological quality of trials. Nevertheless, the efficacy of breast screening for younger women remains controversial. The present controversy has raised other issues like the measure of the benefit in screening trials or the potential adverse effects of screening, particularly, overdiagnosis and its impact on therapy that are discussed in this papers. It also stresses of evaluating screening before introducing it and the need to inform the population about the benefits and the potential harms and about uncertainties about cancer screening
Time-trend and variations in the proportion of second-eye cataract surgery
<p>Abstract</p> <p>Background</p> <p>Despite recommendations for greater use of second-eye cataract surgery and the bilateral progression of the disease, there is a substantial proportion of unmet need for this treatment. Few studies have explored the factors associated with second-eye cataract surgery utilisation. The objective of our study was to estimate the proportion of second-eye cataract surgery, evaluate its time-trend, and explore differences in utilisation by patients' gender, age, and region of residence.</p> <p>Methods</p> <p>All senile cataract surgeries performed between 1999 and 2002 in the public health system of Catalonia (Spain) were obtained from the Minimum Data Set. The proportion of second-eye surgery from November 2000 to December 2002 was calculated. The time-trend of this proportion was characterised through linear regression models with the logarithmic transformation of time.</p> <p>Results</p> <p>The proportion of second-eye surgery was 30.0% and showed an increasing trend from 24.8% (95% Confidence Interval [CI] 21.6; 26.1) in November 2000 to 31.8% (95% CI 31.4; 33.6) in December 2002. This proportion was 1.9% (95% CI 0.9; 2.9) higher in women (p < 0.001) and held constant across time. Male patients aged less than 60 had the lowest proportion (22.6%; 95% CI 22.4; 22.9) and females between 70 and 79 had the highest proportion (27.4%; 95% CI 26.9; 27.9). The time-trend for the proportion of second-eye surgery in those aged over 80 years was greater than for younger ages, showing an increase of 9% at the end of the period for both males and females. Variations between regions decreased over time because regions with the lowest initial proportions of second-eye surgery (approximately 17%) showed a greater increase over the study period.</p> <p>Conclusion</p> <p>We predict greater utilization of second-eye surgery in patients aged 70 to 79 years and in women. A greater increase in the utilisation rates of second-eye surgery is expected in the regions with lower proportions and in older patients. The observed trend suggests that there will be a substantial proportion of unmet need for bilateral surgery.</p
Modelling mutational landscapes of human cancers in vitro
Experimental models that recapitulate mutational landscapes of human cancers are needed to decipher the
rapidly expanding data on human somatic mutations. We demonstrate that mutation patterns in
immortalised cell lines derived from primary murine embryonic fibroblasts (MEFs) exposed in vitro to
carcinogens recapitulate key features of mutational signatures observed in human cancers. In experiments
with several cancer-causing agents we obtained high genome-wide concordance between human tumour
mutation data and in vitro data with respect to predominant substitution types, strand bias and sequence
context. Moreover, we found signature mutations in well-studied human cancer driver genes. To explore
endogenous mutagenesis, we used MEFs ectopically expressing activation-induced cytidine deaminase
(AID) and observed an excess of AID signature mutations in immortalised cell lines compared to their
non-transgenic counterparts. MEF immortalisation is thus a simple and powerful strategy for modelling
cancer mutation landscapes that facilitates the interpretation of human tumour genome-wide sequencing
data
Structure of the mantle beneath the Alboran Basin from Magnetotelluric Soundings
We present results of marine MT acquisition in the Alboran sea that also incorporates previously acquired land MT from southern Spain into our analysis. The marine data show complex MT response functions with strong distortion due to seafloor topography and the coastline, but inclusion of high resolution topography and bathymetry and a seismically defined sediment unit into a 3‐D inversion model has allowed us to image the structure in the underlying mantle. The resulting resistivity model is broadly consistent with a geodynamic scenario that includes subduction of an eastward trending plate beneath Gibraltar, which plunges nearly vertically beneath the Alboran. Our model contains three primary features of interest: a resistive body beneath the central Alboran, which extends to a depth of ∼150 km. At this depth, the mantle resistivity decreases to values of ∼100 Ohm‐m, slightly higher than those seen in typical asthenosphere at the same depth. This transition suggests a change in slab properties with depth, perhaps reflecting a change in the nature of the seafloor subducted in the past. Two conductive features in our model suggest the presence of fluids released by the subducting slab or a small amount of partial melt in the upper mantle (or both). Of these, the one in the center of the Alboran basin, in the uppermost‐mantle (20-30 km depth) beneath Neogene volcanics and west of the termination of the Nekkor Fault, is consistent with geochemical models, which infer highly thinned lithosphere and shallow melting in order to explain the petrology of seafloor volcanics
Effect of oral anticoagulants on the outcome of faecal immunochemical test
Background:
We aimed to evaluate whether oral anticoagulants (OACs) alter faecal immunochemical test (FIT) performance in average-risk colorectal cancer (CRC) screening.
Methods:
Individuals aged 50–69 years were invited to receive one FIT sample (cutoff 75¿ng¿ml–1) between November 2008 and June 2011.
Results:
Faecal immunochemical test was positive in 9.3% (21 out of 224) of users of OAC and 6.2% (365 out of 5821) of non-users (P-trend=0.07). The positive predictive value (PPV) for advanced neoplasia (AN) in non-users was 50.4% vs 47.6% in users (odds ratio, 0.70; 95% CI, 0.3–1.8; P=0.5). The PPV for AN in OAC more antiplatelets (aspirin or clopidogrel) was 75% (odds ratio, 2; 95% CI, 0.4–10.8; P=0.4).
Conclusions:
Oral anticoagulant did not significantly modify the PPV for AN in this population-based colorectal screening program. The detection rate of advanced adenoma was higher in the combination OAC more antiplatelets
Association between Radiologists' Experience and Accuracy in Interpreting Screening Mammograms
<p>Abstract</p> <p>Background</p> <p>Radiologists have been observed to differ, sometimes substantially, both in their interpretations of mammograms and in their recommendations for follow-up. The aim of this study was to determine how factors related to radiologists' experience affect the accuracy of mammogram readings.</p> <p>Methods</p> <p>We selected a random sample of screening mammograms from a population-based breast cancer screening program. The sample was composed of 30 women with histopathologically-confirmed breast cancer and 170 women without breast cancer after a 2-year follow-up (the proportion of cancers was oversampled). These 200 mammograms were read by 21 radiologists routinely interpreting mammograms, with different amount of experience, and by seven readers who did not routinely interpret mammograms. All readers were blinded to the results of the screening. A positive assessment was considered when a BI-RADS III, 0, IV, V was reported (additional evaluation required). Diagnostic accuracy was calculated through sensitivity and specificity.</p> <p>Results</p> <p>Average specificity was higher in radiologists routinely interpreting mammograms with regard to radiologists who did not (66% vs 56%; p < .001). Multivariate analysis based on routine readers alone showed that specificity was higher among radiologists who followed-up cases for which they recommended further workup (feedback) (OR 1.37; 95% CI 1.03 to 1.85), those spending less than 25% of the working day on breast radiology (OR 1.49; 95% CI 1.18 to 1.89), and those aged more than 45 years old (OR 1.33; 95% CI 1.12 to 1.59); the variable of average annual volume of mammograms interpreted by radiologists, classified as more or less than 5,000 mammograms per year, was not statistically significant (OR 1.06; 95% CI 0.90 to 1.25).</p> <p>Conclusion</p> <p>Among radiologists who read routinely, volume is not associated with better performance when interpreting screening mammograms, although specificity decreased in radiologists not routinely reading mammograms. Follow-up of cases for which further workup is recommended might reduce variability in mammogram readings and improve the quality of breast cancer screening programs.</p
Media Systems and the Political Information Environment: A Cross-National Comparison
To express attitudes and act according to their self-interest, citizens need relevant, up-to-date information about current affairs. But has the increased commercialization in the media market increased or decreased the flow of political information? Hallin and Mancini stress that the existing empirical evidence is fragmented and that this question therefore has been difficult to answer. In this article the authors present new data that allow them to systematically examine how the flow of political information on TV occurs across six Western countries during a thirty-year period. The authors find that the flow of political information through TV varies according to the degree of commercialization. The flow of news and current affairs is lowest in the most commercially oriented television system and among the commercial TV channels. There is however important cross-national variation even within similar media systems. The authors’ data do not suggest a convergence toward the liberal system when it comes to the political information environment on TV. Rather, what strikes them is how strongly resistant some European countries have been to subordinating the needs of democracy to profit making
Three-year outcome after transanal versus laparoscopic total mesorectal excision in locally advanced rectal cancer : a multicenter comparative analysis
Altres ajuts: This work has been funded by the Resident Award "Emili Letang," granted by Hospital Clinic of Barcelona, Research, Innovation, and Education Departments (Grant number: 25_delacyoliverb_250709_cgicm_pfr2018). The funder of this study supported the data collection and database management.For patients with mid and distal rectal cancer, robust evidence on long-term outcome and causal treatment effects of transanal total mesorectal excision (TaTME) is lacking. This multicentre retrospective cohort study aimed to assess whether TaTME reduces locoregional recurrence rate compared to laparoscopic total mesorectal excision (LapTME). Consecutive patients with rectal cancer within 12 cm from the anal verge and clinical stage II-III were selected from three institutional databases. Outcome after TaTME (Nov 2011 - Feb 2018) was compared to a historical cohort of patients treated with LapTME (Jan 2000 - Feb 2018) using the inverse probability of treatment weights method. The primary endpoint was three-year locoregional recurrence. A total of 710 patients were analysed, 344 in the TaTME group and 366 in the LapTME group. At 3 years, cumulative locoregional recurrence rates were 3.6% (95% CI, 1.1-6.1) in the TaTME group and 9.6% (95% CI, 6.5-12.7) in the LapTME group (HR = 0.4; 95% CI, 0.23-0.69; p = 0.001). Three-year cumulative disease-free survival rates were 74.3% (95% CI, 68.8-79.8) and 68.6% (95% CI, 63.7-73.5) (HR = 0.82; 95% CI, 0.65-1.02; p = 0.078) and three-year overall survival 87.2% (95% CI, 82.7-91.7) and 82.2% (95% CI, 78.0-86.2) (HR = 0.74; 95% CI, 0.53-1.03; p = 0.077), respectively. In patients who underwent sphincter preservation procedures, TaTME was associated with a significantly better disease-free survival (HR = 0.78; 95% CI, 0.62-0.98; p = 0.033). These findings suggest that TaTME may improve locoregional recurrence and disease-free survival rates among patients with mid and distal locally advanced rectal cancer
BMP2/BMP4 colorectal cancer susceptibility loci in northern and southern european populations
Genome-wide association studies have successfully identified 20 colorectal cancer susceptibility loci. Amongst these, four of the signals are defined by tagging single nucleotide polymorphisms (SNPs) on regions 14q22.2 (rs4444235 and rs1957636) and 20p12.3 (rs961253 and rs4813802). These markers are located close to two of the genes involved in bone morphogenetic protein (BMP) signaling (BMP4 and BMP2, respectively). By investigating these four SNPs in an initial cohort of Spanish origin, we found substantial evidence that minor allele frequencies (MAFs) may be different in northern and southern European populations. Therefore, we genotyped three additional southern European cohorts comprising a total of 2028 cases and 4273 controls. The meta-analysis results show that only one of the association signals (rs961253) is effectively replicated in the southern European populations, despite adequate power to detect all four. The other three SNPs (rs4444235, rs1957636 and rs4813802) presented discordant results in MAFs and linkage disequilibrium patterns between northern and southern European cohorts. We hypothesize that this lack of replication could be the result of differential tagging of the functional variant in both sets of populations. Were this true, it would have complex consequences in both our ability to understand the nature of the real causative variants, as well as for further study designs
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