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861.
Introduction Local excision is considered inappropriate treatment for T3–T4 rectal adenocarcinomas, as it cannot provide prognostic information regarding lymph node involvement and has a high risk of pelvic recurrence. Preoperative chemoradiation (CRT) studies in rectal cancer suggest that a pathological complete response (pCR) in the primary tumour provides an excellent long-term outcome. If downstaging to stage pT0 predicts a tumour response within the perirectal and pelvic lymph nodes, this may allow local excision to be performed without increased risk of pelvic recurrence. This retrospective study aimed to determine the incidence of involved lymph nodes following pCR (ypT0) after preoperative CRT and total mesorectal excision.Method The outcome and treatment details of 211 patients undergoing preoperative CRT for clinically staged T3–T4 unresectable rectal adenocarcinomas between 1993 and 2003 at Mount Vernon Hospital were reviewed.Results Data were recorded from the 143 patients who completed treatment with a median follow-up of 25 months. Twenty-three patients (18%) were found to have had a pCR. Four out of 23 patients (17%) had involved lymph nodes. No pelvic recurrences developed after a ypCR. Overall survival was similar for patients with ypT0 or residual tumour.Conclusion Pathological complete response in the primary tumour failed to predict a response in the perirectal lymph nodes (p=0.08). The degree of response predicted a lymph node response (p=0.02). The detection of ypCR identified patients with a low rate of pelvic recurrence. This may in the future allow selection of patients for whom local excision can be performed without a higher risk of local relapse.On behalf of the Mount Vernon Colorectal Cancer Network  相似文献   
862.
We describe an MRI-based system for topological analysis followed by measurements of topographic features for the human cerebral cortex that takes as its starting point volumetric segmentation data. This permits interoperation between volume-based and surface-based topographic analysis and extends the functionality of many existing segmentation schemes. We demonstrate the utility of these operations in individual as well as to group analysis. The methodology integrates analyses of cortical segmentation data generated by manual and semi-automated volumetric morphometry routines (such as the program cardviews) with the procedures of the FreeSurfer program to generate a cortical ribbon of the cerebrum and perform cortical topographic measurements (including thickness, surface area and curvature) in individual subjects as well as in subject populations. This system allows the computation of topographical cortical measurements for segmentation data generated from manual and semi-automated volumetric sources other than FreeSurfer. These measurements can be regionally specific and integrated with systems of cortical parcellation that subdivides the neocortex into gyral-based parcellation units (PUs). This system of topographical analysis of the cerebral cortex is consistent with current views of cortical development and neural systems organization of the human and non-human primate brain.  相似文献   
863.
The etiology and consistency of findings on normal sexual dimorphisms of the adult human brain are unresolved. In this study, we present a comprehensive evaluation of normal sexual dimorphisms of cortical and subcortical brain regions, using in vivo magnetic resonance imaging, in a community sample of 48 normal adults. The men and women were similar in age, education, ethnicity, socioeconomic status, general intelligence and handedness. Forty-five brain regions were assessed based on T(1)-weighted three-dimensional images acquired from a 1.5 T magnet. Sexual dimorphisms of adult brain volumes were more evident in the cortex, with women having larger volumes, relative to cerebrum size, particularly in frontal and medial paralimbic cortices. Men had larger volumes, relative to cerebrum size, in frontomedial cortex, the amygdala and hypothalamus. A permutation test showed that, compared to other brain areas assessed in this study, there was greater sexual dimorphism among brain areas that are homologous with those identified in animal studies showing greater levels of sex steroid receptors during critical periods of brain development. These findings have implications for developmental studies that would directly test hypotheses about mechanisms relating sex steroid hormones to sexual dimorphisms in humans.  相似文献   
864.
865.
White matter hyperintensities (WMH) are a typical feature of cerebral small vessel disease (CSVD), which contributes to about 50% of dementias worldwide. Microstructural alterations in deep white matter (DWM) have been widely examined in CSVD. However, little is known about abnormalities in superficial white matter (SWM) and their relevance for processing speed, the main cognitive deficit in CSVD. In 141 CSVD patients, processing speed was assessed using Trail Making Test Part A. White matter abnormalities were assessed by WMH burden (volume on T2‐FLAIR) and diffusion MRI measures. SWM imaging measures had a large contribution to processing speed, despite a relatively low SWM WMH burden. Across all imaging measures, SWM free water (FW) had the strongest association with processing speed, followed by SWM mean diffusivity (MD). SWM FW was the only marker to significantly increase between two subgroups with the lowest WMH burdens. When comparing two subgroups with the highest WMH burdens, the involvement of WMH in the SWM was accompanied by significant differences in processing speed and white matter microstructure. Mediation analysis revealed that SWM FW fully mediated the association between WMH volume and processing speed, while no mediation effect of MD or DWM FW was observed. Overall, results suggest that the SWM has an important contribution to processing speed, while SWM FW is a sensitive imaging marker associated with cognition in CSVD. This study extends the current understanding of CSVD‐related dysfunction and suggests that the SWM, as an understudied region, can be a potential target for monitoring pathophysiological processes.  相似文献   
866.
Post-discharge thromboprophylaxis in patients admitted with COVID-19 remains controversial. We aimed to determine the impact of thromboprophylaxis on hospital acquired thrombosis (HAT) in patients (≥18 years) discharged following admission for COVID-19 in an observational study across 26 NHS Trusts in the UK (01.04.2020–31.12.2021). Overall, 8895 patients were included to the study: 971 patients were discharged with thromboprophylaxis and propensity score matched (PSM) with a desired ratio of 1:1, from patients discharged without thromboprophylaxis. Patients with heparin induced thrombocytopenia, major bleeding during admission and pregnant women were excluded. As expected from 1:1 PSM, no difference was observed in parameters between the two groups, including duration of hospital stay, except the thromboprophylaxis group had a significantly higher proportion who had received therapeutic dose anticoagulation during admission. There were no differences in the laboratory parameters especially D-dimers between the two groups at admission or discharge. Median duration of thromboprophylaxis following discharge from hospital was 4 weeks (1–8 weeks). No difference was found in HAT in patients discharged with TP versus no TP (1.3% vs. 0.92%, p = 0.52). Increasing age and smoking significantly increased the risk of HAT. Many patients in both cohorts had raised D-dimer at discharge but D-dimer was not associated with increased risk of HAT.  相似文献   
867.
Background

Body weight loss (BWL) is a negative prognostic factor in metastatic gastric or gastroesophageal junction cancer (mGC/GEJC). In the phase III TAGS study, trifluridine/tipiracil improved survival versus placebo in third- or later-line mGC/GEJC. These retrospective analyses examined the association of early BWL with survival outcomes in TAGS.

Methods

Efficacy and safety were assessed in patients who experienced < 3% or ≥ 3% BWL from treatment start until day 1 of cycle 2 (early BWL). The effect of early BWL on overall survival (OS) was assessed by univariate and multivariate analyses.

Results

Body weight data were available for 451 of 507 (89%) patients in TAGS. In the trifluridine/tipiracil and placebo arms, respectively, 74% (224/304) and 65% (95/147) experienced < 3% BWL, whereas 26% (80/304) and 35% (52/147) experienced ≥ 3% BWL at cycle 1 end. Median OS was longer in < 3% BWL versus ≥ 3% BWL subgroups (6.5 vs 4.9 months for trifluridine/tipiracil; 6.0 vs 2.5 months for placebo). In univariate analyses, an unadjusted HR of 0.58 (95% CI, 0.46–0.73) for the < 3% vs ≥ 3% BWL subgroup indicated a strong prognostic effect of early BWL. Multivariate analyses confirmed early BWL as both prognostic (P < 0.0001) and predictive (interaction P = 0.0003) for OS. Similar results were obtained for progression-free survival. Any-cause grade ≥ 3 adverse events were reported in 77% and 82% of trifluridine/tipiracil-treated and 45% and 67% of placebo-treated patients with < 3% and ≥ 3% BWL, respectively.

Conclusions

In TAGS, early BWL was a strong negative prognostic factor for OS in patients with mGC/GEJC receiving third- or later-line treatment.

  相似文献   
868.
869.

Introduction

Recent guidelines for von Willebrand Disease (VWD) highlighted the challenges in diagnosis and management. Identifying the number of persons with VWD (PwVWD) internationally will help target support to aid diagnosis of PwVWD.

Aim

To examine international registration rates of PwVWD, the influence of income status, geographical region and the age and sex profile. Cumulatively, these data will be used to inform future strategy from the World Federation of Haemophilia (WFH) to address unmet clinical and research needs.

Methods

Data from the 2018/2019 WFH Annual Global Survey (AGS) were analysed, providing a global perspective on VWD registration.

Results

Registration rates are lowest in South Asia (0.6/million population) and highest in Europe/Central Asia (50.9/million population, 0.005%), but below the expected prevalence rate (0.1%). National economic status impacted VWD registration rates, reflecting variation in access to optimal healthcare infrastructure. Females represented the majority of PwVWD globally, however, in low-income countries (LIC) males predominated. Age profile varied, with markedly higher rates of paediatric registrations in North America, Middle East and North Africa and South Asia. Rates of type 3 VWD registrations were significantly influenced by economic status (81% of VWD diagnoses in LIC), suggesting only the most severe VWD types are diagnosed in resource limited settings.

Conclusion

Significant variation in registration rates of PwVWD exist internationally and is influenced by income status and the presence of HTC networks. Improved understanding of registration rates will enable targeting of advocacy to improve awareness, diagnosis and support for PwVWD internationally.

Key points

  • Registration rates of People with Von Willebrand Disease (PwVWD) vary internationally and are influenced by national income status
  • Although females represent the majority of PwVWD globally, in low income countries (LIC) males predominated, possibly related to stigma surrounding gynaecological bleeding.
  • Rates of type 3 VWD registration were significantly influenced by economic status (81% of VWD diagnoses in LIC), suggesting only the most severe VWD types are diagnosed in resource limited settings.
  相似文献   
870.
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