Aggarwal, Manik

Background: Fluorescence in situ hybridization (FISH) is recommended as part of multimodality sampling in the evaluation of biliary strictures, but can be false negative in 40%–50% cases. The aim of this study was to comprehensively assess predictors of false-negative FISH in patients with biliary strictures. Methods: Patients undergoing tissue sampling for biliary strictures from October 20 to February 22 were prospectively enrolled (NCT04572711). Procedural factors such as sampling techniques, order, and utilization of combination sampling were recorded. Results of an optimized pancreatobiliary FISH panel with locus-specific probes for 1q21, 7p12, 8q24, and 9p21 were reported per guidelines. Statistical analyses were performed using BlueSky Statistics v.10.3.1, R package v8.81. Results: Of 327 patients, 93 (28.5%) were diagnosed with malignancy. A false-negative pancreatobiliary fluorescence in situ hybridization (PB-FISH) was reported in 40 (43.1%) patients. A history of primary sclerosing cholangitis was associated with lower odds of having a false-negative PB-FISH (aOR=0.38, 95% CI=0.16–0.82, p=0.02), whereas a hilar stricture was associated with a significantly higher false-negative PB-FISH in those with cholangiocarcinoma (aOR=3.2 [1.4–7.9], p=0.009). Dilation of biliary strictures prior to brushing was not associated with a lower rate of false-negative PB-FISH. Conclusions: In this prospective study, hilar strictures were more likely to have false-negative PB-FISH. Dilation of strictures did not affect PB-FISH performance. These results can help guide PB-FISH interpretation.

Endoscopic ultrasound (EUS)-guided tissue sampling includes the techniques of fine needle aspiration (FNA) and fine needle biopsy (FNB), and both procedures have revolutionized specimen collection from the gastrointestinal tract, especially from remote/inaccessible organs. EUS-FNB has replaced FNA as the procedure of choice for tissue acquisition in solid pancreatic lesions (SPLs) across various society guidelines. FNB specimens provide a larger histological tissue core (preserving tissue architecture) with fewer needle passes, and this is extremely relevant in today’s era of precision and personalized molecular medicine. Innovations in needle tip design are constantly under development to maximize diagnostic accuracy by enhancing histological sampling capabilities. But, apart from the basic framework of the needle, various other factors play a role that influence diagnostic outcomes, namely, sampling techniques (fanning, aspiration or suction, and number of passes), collection methods, on-site evaluation (rapid, macroscopic, or visual), and specimen processing. The choice taken depends strongly on the endoscopist’s preference, available resources at the disposal, and procedure objectives. Hence, in this review, we explicate in detail the concepts and available literature at our disposal on the topic of EUS-guided pancreatic tissue sampling to best guide any practicing gastroenterologist/endoscopist in a not-to-ideal set-up, which EUS-guided tissue acquisition technique is the “best” for their case to augment their diagnostic outcomes.

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally in tandem with the growing obesity epidemic. However, there is a lack of data on the relationship between historical weight changes 10 years ago and at present on NAFLD prevalence at the population level. Therefore, we sought to evaluate the relationship between weight classes and the prevalence of NAFLD. Methods: Data were used from the United States National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Univariate and multivariate general linear model analyses were used to obtain risk ratio (RR) estimations of NAFLD events. Results: In total, 34,486 individuals were analysed, with those who were lean at both time points as the control group. Overweight (RR: 14.73, 95%CI: 11.94 to 18.18, p < 0.01) or obese (RR: 31.51, 95%CI: 25.30 to 39.25, p < 0.01) individuals at both timepoints were more likely to develop NAFLD. Residual risk exists where previously obese individuals became overweight (RR: 14.72, 95%CI: 12.36 to 17.52, p < 0.01) or lean (RR: 2.46, 95%CI: 1.40 to 4.31, p = 0.02), and previously overweight individuals who became lean (RR 2.24, 95%CI 1.42 to 3.54, p = 0.01) had persistent elevated risk of developing NAFLD despite weight regression. Sensitivity analysis identified that a higher proportion of individuals with regression in weight class were diabetics and Mexican Americans, while fewer African Americans saw weight-class regression. Conclusions: Residual risk exists in patients who lost weight despite the smaller magnitude of effect, and targeted weight reductions should still be used to mitigate the risk of NAFLD at the population level.