Young GI Angle: highlights of UEG Week 2019

Linked colour imaging better than white light to detect early neoplasms

A multicentre randomized control clinical trial (RCT) from China¹ assessed the effectiveness of linked colour imaging (LCI) in early gastric cancer. These authors randomly allocated patients who underwent upper-GI endoscopy into white light (WL) endoscopy alone (n = 914) or combined with LCI (n = 914). LCI achieved a higher accuracy for detecting gastric intestinal metaplasia (88% vs. 68%) and early gastric cancer or high-grade intraepithelial neoplasms (77% vs. 66%) compared to WL alone, suggesting that this modality could improve the diagnostic accuracy in this scenario.

Similarly, Paggi et al.,² in a multicentre RCT in a colorectal cancer screening programme, analysed the effectiveness of WL compared to LCI. The main aim was the proportion of patients with at least one adenoma. There were 649 randomised patients stratified by gender, age and screening round. The adenoma detection was higher in the LCI group (57% vs. 44%, p = 0.047), without statistically significant differences for the detection of advanced adenomas.

Computer-aided detection help to characterize colorectal lesions

Another RCT³ comparatively evaluated the adenoma detection rate between colonoscopy with or without the assistance of a real-time computer-aided detection (CAD) system. This trial included 790 patients in two arms and concluded that there were differences in polyp (33% vs. 47%, p < 0.001) and adenoma detection rates (29% vs. 21%, p = 0.009). The AI-aided endoscopic diagnosis systems can also be accurate in the characterization of colorectal lesions in real-time.

A prospective observational study from Japan⁴ including 102 polyps in 30 patients, reported that the CAD-system detected 95 polyps (93%) and was able to predict differential diagnosis (neoplastic/non-neoplastic) in 58 polyps from 81 resected with an accuracy and positive predictive value of 87% and 93% respectively. These results may be comparable to endoscopists in a real-time clinical setting.

Regarding indeterminate biliary strictures, single-operator cholangioscopy guided biopsy is an emerging technique that has shown to be both safe and effective. This procedure has been proposed as an alternative to standard endoscopic retrograde cholangiopancreatography (ERCP) guided brushing. Gerges C et al.,⁵ in a multicentre RCT including 61 patients, comparatively analysed the diagnostic accuracy of both techniques based on histopathology as gold standard. The sensitivity of SOC-guided biopsies was significantly higher compared to ERCP-guided brushing (68% vs. 21%, p < 0.01), but there were no significant differences in overall accuracy.

Endoscopy-based interventions for the treatment of infected necrotizing pancreatitis reduces complications

Finally, concerning endoscopic ultrasound guided therapies, a systematic review and meta-analysis of three RCTs presented by Bang et al.,⁶ from USA, compared minimally invasive surgery and endoscopy-based interventions for the treatment of infected necrotizing pancreatitis. The main outcome measures were the complication rate or death during 6-months follow-up. This study pooled 184 patients concluding that there were no differences in mortality between both approaches (15% vs. 16%, p = 0.96). However, endoscopy-based techniques achieved a lower new onset multiple organ failure (5% vs. 20%, relative risk [RR]: 0.34, p = 0.045), enterocutaneous fistula/perforation (4% vs. 18%, RR = 0.34, p = 0.034) and pancreatic fistula (4% vs. 38%, RR = 0.13, p < 0.001) compared to surgery. Also, the length of hospital stay was lower. These results confirmed that endoscopy significantly reduces complications in patients with infected necrotizing pancreatitis.

Obeticholic acid, a new treatment for NASH

The month 18 pre-specified interim analysis of the ongoing Phase 3 REGENERATE randomized study that evaluates the effect of obeticholic acid (OCA), an FXR agonist, on liver histology in 931 patients with biopsy confirmed NASH was presented during the meeting.⁷ Fibrosis primary endpoint (fibrosis improvement (≥1 stage) with no worsening of NASH) was met by 12% placebo and 23% OCA 25 mg patients (p = 0.0002). Pruritus was the most common adverse event and led to the discontinuation of the drug in 9% of OCA 25 mg treated patients. Thus, treatment with OCA 25 mg improved liver fibrosis and key histologic features of NASH with an overall adverse event rate similar to previous studies.

Identification of risk factors for early portal thrombosis after liver transplantation

A post-hoc analysis of a prospective cohort of 748 patients who underwent liver transplantation (LT) in The Netherlands demonstrated that smoking status and some genetic variation of the donor as well as the presence of NASH in the recipient were associated with early portal thrombosis occurrence.⁸

Assessment of sarcopenia using volumetric computerized tomography

In a retrospective Italian study that included 80 patients who underwent LT, volumetric cut-offs of indexed abdominal muscle volume of 583.7 cm³ /m² for women and 629.9 cm³ /m² for men were associated with sarcopenia and with high risk of death after LT.⁹ However, furthers studies are needed to compare the diagnosis performance of the volumetric-CT analysis proposed by the authors to the single-CT slice at L3 level, the actual standard analysis.

Outcome of hepatocellular adenomas (HCA) screened by magnetic resonance imaging (MRI)

A retrospective multicenter study of 118 patients with pathology-proven HCA who underwent MRI surveillance with a median follow-up of 5 years showed that 78% of HCA presented long-term stability or regression. After resection of solitary HCA, tumor progression occurred only in HCA at-risk of malignancy. Patients with multiples HCA were more likely to show progressive disease, with HNF-1α inactivated HCAs being the most common subtype showing progression.¹⁰ This study suggested that the genotype/phenotype classification based on tissue analysis but also on MRI could be useful to stratify the treatment of patients with HCA in routine.

Liver disorders induced by immunotherapy

In this retrospective study from Japan, 8% of 103 patients (63% of them with lung cancer) treated with Nivolumab and/or Pembrolizumab (anti PD-1/PD-L1 antibody) presented liver disorders (4% of grade 3). Immunotherapy was continued in patients with mild liver disorders without aggravation. The outcome of patients with severe liver disorders was good after discontinuation of the treatment and administration of immunosuppressive agents such as corticosteroids.¹¹ Thus, early management of liver disorders induced by immune checkpoint inhibitors is associated with a good outcome.

Quick removal of endoscopic biliary drainage after IgG4 related sclerosing cholangitis clinical remission

In this retrospective study of 70 patients with IgG4 related sclerosing cholangitis, Miyazawa et al. suggested that endoscopic biliary drainage removal should be carried out within 2-3 weeks after corticosteroids initiation to prevent endoscopic biliary drainage detachment in patients who achieved clinical remission by corticosteroid treatment.¹²