Evaluation of the effectiveness of endoscopic retrograde cholangiopancreatography in patients with perihilar cholangiocarcinoma and its effect on development of cholangitis

Development and validation of a risk score for predicting clinical success after endobiliary stenting for malignant biliary obstruction

Background

Endoscopic drainage is the primary treatment for unresectable malignant biliary obstruction (MBO). This study developed and validated a pre-endoscopic predictive score for clinical success after stent placement.

Methods

Patients with unresectable MBO undergoing ERCP-guided endobiliary stent placement between 2007 and 2017 were randomly divided into derivation (n = 383) and validation (n = 128) cohorts. To develop the risk score, clinical parameters were built by logistic regression to predict (1) ≥ 50% total bilirubin (TB) resolution within 2 weeks and (2) bilirubin normalization (TB level <1.2 mg/dL) within 6 weeks following stenting. The scoring scheme was applied to the validation cohort to test its performance.

Results

A ≥ 50% TB resolution within 2 weeks was shown in 70.5% of cases. The risk scoring scheme had areas under the receiver operating characteristic curve (AUROC) of 0.70 (95% CI, 0.64–0.76) and 0.67 (95% CI, 0.57–0.77) in the derivation and validation cohorts, respectively. Thirty-one percent had TB normalization within 6 weeks after stenting. Significant predictors for TB normalization were extrahepatic biliary obstruction (odds ratio [OR] = 2.35), pre-endoscopic TB level (OR = 0.88), and stent type (OR = 0.42). The AUROC of a risk score for predicting TB normalization within 6 weeks was 0.78 (95% CI, 0.72–0.83) and 0.76 (95% CI, 0.67–0.86) in the derivation and validation cohorts, respectively. A score > 1.30 yielded a specificity of 98% and a positive predictive value of 84% for predicting TB normalization. A score of < -4.18 provided a sensitivity of 80%–90% and a negative predictive value of 90%–93% for predicting the absence of TB normalization.

Conclusions

The pre-endoscopic scoring system comprising biliary obstruction level, liver biochemistry, and type of stent provides prediction indices for TB normalization within 6 weeks after stenting. This scheme may help endoscopists identify patients with unresectable MBO suited for palliative stenting.

Endoscopic or percutaneous biliary drainage in hilar cholangiocarcinoma: When and how?

Hilar cholangiocarcinoma (hCCA) is a primary liver tumor associated with a dim prognosis. The role of preoperative and palliative biliary drainage has long been debated. The most common techniques are endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic biliary drainage (PTBD); however, recently developed endoscopic ultrasound-assisted methods are gaining more atention. Selecting the best available method in any specific scenario is crucial, yet sometimes challenging. Thus, this review aimed to discuss the available techniques, indications, perks, pitfalls, and timing-related issues in the management of hCCA. In a preoperative setting, PTBD appears to have some advantages: low risk of postprocedural complications (namely cholangitis) and better priming for surgery. For palliative purposes, we propose ERCP/PTBD depending on the experience of the operators, but also on other factors: the level of bilirubin (if very high, rather PTBD), length of the stenosis and the presence of cholangitis (PTBD), ERCP failure, or altered biliary anatomy.

Endoscopic or percutaneous biliary drainage in hilar cholangiocarcinoma: When and how?

Hilar cholangiocarcinoma (hCCA) is a primary liver tumor associated with a dim prognosis. The role of preoperative and palliative biliary drainage has long been debated. The most common techniques are endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic biliary drainage (PTBD); however, recently developed endoscopic ultrasound-assisted methods are gaining more atention. Selecting the best available method in any specific scenario is crucial, yet sometimes challenging. Thus, this review aimed to discuss the available techniques, indications, perks, pitfalls, and timing-related issues in the management of hCCA. In a preoperative setting, PTBD appears to have some advantages: low risk of postprocedural complications (namely cholangitis) and better priming for surgery. For palliative purposes, we propose ERCP/PTBD depending on the experience of the operators, but also on other factors: the level of bilirubin (if very high, rather PTBD), length of the stenosis and the presence of cholangitis (PTBD), ERCP failure, or altered biliary anatomy.

Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts

Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities.

Metagenomic sequencing of bile from gallstone patients to identify different microbial community patterns and novel biliary bacteria

Despite the high worldwide prevalence of gallstone disease, the role of the biliary microbiota in gallstone pathogenesis remains obscure. Next-generation sequencing offers advantages for systematically understanding the human microbiota; however, there have been few such investigations of the biliary microbiome. Here, we performed whole-metagenome shotgun (WMS) sequencing and 16S rRNA sequencing on bile samples from 15 Chinese patients with gallstone disease. Microbial communities of most individuals were clustered into two types, according to the relative enrichment of different intestinal bacterial species. In the bile samples, oral cavity/respiratory tract inhabitants were more prevalent than intestinal inhabitants and existed in both community types. Unexpectedly, the two types were not associated with fever status or surgical history, and many bacteria were patient-specific. We identified 13 novel biliary bacteria based on WMS sequencing, as well as genes encoding putative proteins related to gallstone formation and bile resistance (e.g., β-glucuronidase and multidrug efflux pumps). Bile samples from gallstone patients had reduced microbial diversity compared to healthy faecal samples. Patient samples were enriched in pathways related to oxidative stress and flagellar assembly, whereas carbohydrate metabolic pathways showed varying behaviours. As the first biliary WMS survey, our study reveals the complexity and specificity of biliary microecology.

The effects of different preoperative biliary drainage methods on complications following pancreaticoduodenectomy

The objective of this study was to investigate the effects of different preoperative biliary drainage (PBD) methods on complications in jaundiced patients following pancreaticoduodenectomy. We retrospectively analyzed 270 extrahepatic bile duct cancer patients who underwent pancreaticoduodenectomy. A total of 170 patients without PBD treatment were defined as the non-PBD group. According to different PBD methods, 45, 18, and 37 patients were classified into the percutaneous transhepatic biliary drainage (PTBD), endoscopic nasobiliary drainage (ENBD), and endoscopic retrograde biliary stent (ERBS) groups, respectively. Clinical characteristics and complications were compared among the 4 groups. Preoperative cholangitis occurred in 14 (8.2%) and 8 (21.6%) patients in the non-PBD and ERBS group, respectively (P = 0.04). Compared with the non-PBD group, delayed gastric emptying (DGE) and wound infection occurred significantly more often in the ERBS group. The incidence of severe complications was significantly lower in the PTBD group than the non-PBD group (P = 0.03). Postoperative hospital stay and complication rates were significantly higher in the ERBS group than the PTBD group. There were no significant differences in complications between ENBD and other groups. In conclusion, PTBD can improve surgical outcomes by reducing severe complication rate in jaundiced patients following pancreaticoduodenectomy. ERBS increased the rates of DGE and wound infection due to high incidence of cholangitis before operative intervention and should be avoided. ENBD carried no special effect on complications and needs further analysis.

Biliary strictures: diagnostic considerations and approach

Biliary strictures present a diagnostic challenge, especially when no etiology can be ascertained after laboratory evaluation, abdominal imaging and endoscopic retrograde cholangiopancreatography (ERCP) sampling. These strictures were traditionally classified as indeterminate strictures, although with advances in endoscopic techniques and better understanding of hepato-biliary pathology, more are being correctly diagnosed. The implications of missing a malignancy in patients with biliary strictures—and hence delaying surgery—are grave but a significant number of patients (up to 20%) undergoing surgery for suspected biliary malignancy can have benign pathology. The diagnostic approach to these patients involves detailed history and physical examination and depends on the presence or absence of jaundice, level of obstruction, and presence or absence of a mass lesion. While abdominal imaging helps to find the level of obstruction and provides a ‘road map' for further endoscopic investigations, tissue diagnosis is usually needed to make decisions on management. Initially ERCP was the only modality to investigate these strictures but now, with the development of endoscopic ultrasound with fine needle aspiration and the availability of newer techniques such as intraductal ultrasound, single-operator cholangioscopy and confocal laser endomicroscopy, the diagnostic approach to biliary strictures has changed significantly. In this review, we will focus on the decision-making process for patients with biliary strictures and discuss the key decision points that should dictate further diagnostic investigations at each step.