Utility of MRI in detection of PET-CT proven local recurrence of pancreatic adenocarcinoma after surgery

The aim of this prospective study was to investigate the accuracy and inter-observer reliability of MRI in detection of local recurrence (LR) of pancreatic adenocarcinoma (PAC) after surgery, which was proved by PET-CT and access correlation between functional MRI and PET parameters. Forty-five patients who underwent PET-CT and MRI for follow-up purposes after radical operation of PAC were included. Twenty-three were PET positive (study group) and 22 negative for LR (control group). MR examination was performed within one month after PET-CT and three readers who were blind for PET-CT findings searched LR in T2W, 3D-dynamic post-contrast T1W-FS and DWI sequences, respectively. Sensitivity and specificity were calculated while inter-reader agreement was estimated by Cronbach's Alpha reliability coefficient (CARC). Apparent diffusion coefficient (ADC) of LR was correlated with the size (maximal diameter) and functional PET-CT parameters: mean and maximum standardized uptake values (SUVmean, SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG), using Spearman's correlation coefficient (rS). Sensitivity and specificity among three readers in detecting the LR were 70% and 77-84% in T2W (CARC 0.806), 91-100% and 100% in 3D post-contrast T1W-FS (CARC 0.980), and both 100% in DWI sequences (CARC 1.000). Moderate inverse correlation was found between the ADC and SUVmean (rS = - 0.484), MTV (rS = - 0.494), TLG (rS = - 0.519) and lesion size (rS = - 0.567). MRI with DWI shows high diagnostic accuracy in detecting the LR of PAC in comparison to PET-CT as reference standard. ADC significantly inversely correlates with standard and advanced PET parameters and size of LR.

Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey

BACKGROUND

Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies.

METHODS

A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies.

RESULTS

Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites.

CONCLUSION

Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

Advanced cardiometabolic & inflammatory markers for prediction of cardiovascular disease and cancer

 

The two leading causes of mortality worldwide are cardiovascular disease (CVD) and cancer. The annual total cost of CVD and cancer is an estimated $844.4 billion in the US and is projected to double by 2030. Thus, there has been an increased shift to preventive medicine to improve health outcomes and development of risk scores, which allow early identification of individuals at risk to target personalised interventions and prevent disease. Our aim was to define a Risk Score R(x) which, given the baseline characteristics of a given individual, outputs the relative risk for composite CVD, cancer incidence and all-cause mortality.

A non-linear model was used to calculate risk scores based on the participants of the UK Biobank (= 502548). The model used parameters including patient characteristics (age, sex, ethnicity), baseline conditions, lifestyle factors of diet and physical activity, blood pressure, metabolic markers and advanced lipid variables, including ApoA and ApoB and lipoprotein(a), as input. The risk score was defined by normalising the risk function by a fixed value, the average risk of the training set. To fit the non-linear model &gt;400,000 participants were used as training set and &gt;45,000 participants were used as test set for validation. The exponent of risk function was represented as a multilayer neural network. This allowed capturing interdependent behaviour of covariates, training a single model for all outcomes, and preserving heterogeneity of the groups, which is in contrast to CoxPH models which are traditionally used in risk scores and require homogeneous groups. The model was trained over 60 epochs and predictive performance was determined by the C-index with standard errors and confidence intervals estimated with bootstrap sampling.

By inputing the variables described, one can obtain personalised hazard ratios for 3 major outcomes of CVD, cancer and all-cause mortality. Therefore, an individual with a risk Score of e.g. 1.5, at any time he/she has 50% more chances than average of experiencing the corresponding event. The proposed model showed the following discrimination, for risk of CVD (C-index = 0.8006), cancer incidence (C-index = 0.6907), and all-cause mortality (C-index = 0.7770) on the validation set. The CVD model is particularly strong (C-index &gt;0.8) and is an improvement on a previous CVD risk prediction model also based on classical risk factors with total cholesterol and HDL-c on the UK Biobank data (C-index = 0.7444) published last year (Welsh et al. 2019). Unlike classically-used CoxPH models, our model considers correlation of variables as shown by the table of the values of correlation in Figure 1.

This is an accurate model that is based on the most comprehensive set of patient characteristics and biomarkers, allowing clinicians to identify multiple targets for improvement and practice active preventive cardiology in the era of precision medicine.

Figure 1. Correlation of variables in the R(x)

Funding Acknowledgement

Type of funding source: None

The effect of elevated triglycerides and purified eicosapentaenoic acid ethyl ester (EPA) for cardiovascular risk reduction in the UK Biobank population

 

Elevated plasma triglycerides (TG) are associated with insulin resistance, metabolic syndrome and major adverse cardiovascular events (MACE). Elevated plasma TG (&gt;150 and 200–499 mg/dL) were recently reported to be a predictor of heart failure in patients with coronary heart disease on statin therapy with a respective 19% and 24% risk increase compared to normal TG levels. REDUCE-IT was a major double-blind randomised controlled trial that tested a novel formulation of highly purified eicosapentaenoic acid ethyl ester (EPA) in 8179 patients with elevated TG on statin therapy. In the trial, daily 4g of EPA lowered MACE by an absolute rate of 4.8% compared to a placebo over a median 4.9-year follow-up. This reflected a 25% risk reduction in MACE and a number needed to treat of 21. EPA recently received significant public attention in late 2019 as the FDA has approved it for secondary prevention and high-risk primary prevention of cardiovascular disease (CVD) in patients with elevated TG that match the trial criteria in the USA. We aimed to investigate the risk reduction in MACE from using EPA in the UK population.

We used the UK BioBank, a panomic resource following 500,000 participants over &gt;10 years, with similar age and sex adjusted rates of CVD as the UK population. We first calculated the hazard ratios and Kaplan-Meier survival curves by deciles of increasing TG for incidence of combined CV outcomes: stroke, coronary heart disease, and atherosclerosis. Non-linear CoxPH and DeepSurvival models were trained using different variables from &gt;200,000 UK BioBank participants' data. C-index with standard error and confidence interval estimated with bootstrap sampling ensured quality control. We then matched the UK Biobank population with the REDUCE-IT inclusion criteria and estimated the reduction of combined cardiovascular outcomes if EPA was approved in this population.

Hazard ratios increased for TG levels to 5.44 between the 10th decile, and the 1st decile TG level, which was used as baseline. 3563 UK Biobank participants matched with the REDUCE-IT criteria. With the assumption that EPA would have the same effect on the UK Biobank population, we estimate that if the participants were taking EPA, only 29% of the risk group versus actual 37% would have suffered an outcome within the UK Biobank follow-up period. This means that 289 less individuals would have suffered an event instead of the recorded 1318, for a total of 1037. That means according to the number needed to treat analysis, 13 patients would need to be treated to prevent 1 patient from experiencing an event.

Elevated TG increase risk for CV events in the UK Biobank population. Purified EPA might become an important tool in our arsenal for CVD secondary and primary prevention.

Survival Curves & CI of TG for CVD

Funding Acknowledgement

Type of funding source: None