A critical review of surgical strategies to minimise venous stenosis in arteriovenous grafts

It is inevitable that complications arising from surgical procedures are ascribed to surgical technique, and this applies to venous stenosis (VS) in arteriovenous grafts. However, despite a wide range of cellular studies, computer modelling, observational series and clinical trials, there remains uncertainty on whether surgical technique contributes to VS. This article reviews evidence from basic science, fluid dynamics and clinical data to try and rationalise the main surgical options to modify the occurrence of venous stenosis. There is sufficient data from diverse sources to make recommendations on clinical practice (size of target vein, shape of anastomosis, angle of approach, distance from venous needling, trauma to the target vein) whilst at the same time this emphasises the need to carefully report the practical aspects of surgical technique in future clinical trials.

Discovering and comparing types of general practitioner practices using geolocational features and prescribing behaviours by means of K-means clustering

Traditionally General Practitioner (GP) practices have been labelled as being in Rural, Urban or Semi-Rural areas with no statistical method of identifying which practices fall into each category. The main aim of this study is to investigate whether location and other characteristics can provide a tautology to identify different types of GP practice and compare the prescribing behaviours associated with the different practice types. To achieve this monthly open source prescription data were analysed by practice considering location, practice size, population density and deprivation rankings. One year’s data was subjected to k-means clustering with the results showing that only two different types of GP practice can be classified that are dependent on location characteristics in Northern Ireland. Traditional labels did not describe the two classifications fully and new classifications of Metropolitan and Non-Metropolitan were used. Whilst prescribing patterns were generally similar, it was found that Metropolitan practices generally had higher prescribing rates than Non-Metropolitan practices. Examining prescribing behaviours in accordance with British National Formulary (BNF) categories (known as chapters) showed that Chapter 4 (Central Nervous System) was responsible for most of the difference in prescribing levels. Within Chapter 4 higher prescribing levels were attributable to Analgesic and Antidepressant prescribing. The clusters were finally examined regarding the level of deprivation experienced in the area in which the practice was located. This showed that the Metropolitan cluster, having higher prescription rates, also had a higher proportion of practices located in highly deprived areas making deprivation a contributing factor.

Biomarker testing in non-small cell lung cancer (NSCLC): An assessment of current practices in precision oncology in the community setting—A trial of the ECOG-ACRIN cancer research group (EAQ161CD).

e18649 Background: Molecular biomarker testing is integral to NSCLC cancer care, but adoption and testing practices in the community are varied and often suboptimal. Testing practices, such as standard testing protocols and results turnaround time (TAT), impact timely treatment decisions. We examined adoption and testing practices for guideline recommended NSCLC biomarkers among National Cancer Institute Community Research Program (NCORP) sites. The study was conducted in collaboration with Wake Forest NCORP Research Base. Methods: An online survey was administered to onsite labs affiliated with NCORP sites April 2019 – June 2020. We assessed testing practices for 7 NCCN recommended biomarkers, including 3 with category 1 recommendation (EGFR, ALK, PD-L1) and 4 with category 2 recommendations (BRAF, ROS1, MET, RET). Guideline concordant result TAT was defined as return of EGFR and ALK results in ≤ 10 days (Lindeman 2018) (see Table for other outcomes). We used proportions, including two-sided Fischer exact tests, to compare outcomes by site characteristics (safety net, practice size). Results: The survey response rate was 69% (58/85). All responding labs offered testing for category 1 biomarkers (EGFR, ALK and PD-L1); only 10% conducted these tests in-house (Table). The majority of labs also tested for category 2 biomarkers (67%). TAT varied, with most labs returning results in ≤ 10 days for EGFR and ALK (69%, but only a minority meet this TAT for all biomarkers. Larger practice size (> 1400 new cancer cases a year) was associated with in-house testing of EGFR, ALK, PD-L1 (p=0.03) and having standard testing protocols (p<0.001). Safety net affiliation did not significantly impact practices. Conclusions: We found universal adoption of NCCN category 1 biomarkers among the labs affiliated with NCORP sites, with the majority meeting guideline concordant results TAT. There is opportunity for improvement in adoption of category 2 biomarkers and result TAT, for example, by using standard testing protocols. Reassuringly, no difference in testing practices was detected by safety net affiliation.[Table: see text]