Risk Factors for Pancreatitis and Cholecystitis after Endoscopic Biliary Stenting in Patients with Malignant Extrahepatic Bile Duct Obstruction

Computed tomography-based prediction of pancreatitis following biliary metal stent placement with the convolutional neural network

Background and study aims Pancreatitis is a potentially lethal adverse event of endoscopic transpapillary placement of a self-expandable metal stent (SEMS) for malignant biliary obstruction (MBO). Deep learning-based image recognition has not been investigated in predicting pancreatitis in this setting. Patients and methods We included 70 patients who underwent endoscopic placement of a SEMS for nonresectable distal MBO. We constructed a convolutional neural network (CNN) model for pancreatitis prediction using a series of pre-procedure computed tomography images covering the whole pancreas (≥ 120,960 augmented images in total). We examined the additional effects of the CNN-based probabilities on the following machine learning models based on clinical parameters: logistic regression, support vector machine with a linear or RBF kernel, random forest classifier, and gradient boosting classifier. Model performance was assessed based on the area under the curve (AUC) in the receiver operating characteristic analysis, positive predictive value (PPV), accuracy, and specificity. Results The CNN model was associated with moderate levels of performance metrics: AUC, 0.67; PPV, 0.45; accuracy, 0.66; and specificity, 0.63. When added to the machine learning models, the CNN-based probabilities increased the performance metrics. The logistic regression model with the CNN-based probabilities had an AUC of 0.74, PPV of 0.85, accuracy of 0.83, and specificity of 0.96, compared with 0.72, 0.78, 0.77, and 0.96, respectively, without the probabilities. Conclusions The CNN-based model may increase predictability for pancreatitis following endoscopic placement of a biliary SEMS. Our findings support the potential of deep learning technology to improve prognostic models in pancreatobiliary therapeutic endoscopy.

Endoscopic Management of Malignant Biliary Obstruction

Endoscopic retrograde cholangiopancreatography (ERCP) is commonly used for managing malignant biliary obstruction; however, it is impossible if the endoscope cannot reach the ampulla of Vater, and it carries a risk of procedure-related pancreatitis. Percutaneous approach is a traditional rescue method when ERCP fails and can be useful in advanced malignant hilar biliary obstruction; however, it is invasive and carries risks of tube dislodgement, recurrent infection, and tract seeding. Endoscopic ultrasound approach may be attempted if ERCP fails and is free from the risk of pancreatitis; however, it is only possible in limited centers, and training is still difficult. Malignant biliary obstruction should be managed by leveraging the complementary strengths of these methods.

Biliary Adverse Events During Neoadjuvant Therapy for Pancreatic Cancer

OBJECTIVE

To describe a high-volume experience with biliary drainage before neoadjuvant therapy (NAT) for patients with operable pancreatic cancer (PC) and characterize the association between biliary adverse events (BAEs) and patient outcome.

BACKGROUND

Patients with PC presenting with biliary obstruction require durable decompression before NAT.

METHODS

Patients with operable PC and tumor-associated biliary obstruction were examined and grouped by the presence or absence of a BAE during NAT. The incidence, timing, and management of BAEs are described, and outcomes, including the completion of all treatment and overall survival (OS), were compared.

RESULTS

Of 426 patients who received pretreatment biliary decompression, 92 (22%) experienced at least 1 BAE during NAT, and 56 (13%) required repeat intervention on their biliary stent. The median duration of NAT was 161 days for all patients and was not different in the group that experienced BAEs. The median time from initial stent placement to BAE was 64 days. An interruption in the delivery of NAT (median 7 days) occurred in 25 (6%) of 426 patients. Among 426 patients, 290 (68%) completed all NAT, including surgery: 60 (65%) of 92 patients with BAE and 230 (69%) of 334 patients without BAE ( P =0.51). Among 290 patients who completed NAT and surgery, the median OS was 39 months, 26 months for the 60 patients with BAE, and 43 months for the 230 patients without BAE ( P =0.02).

CONCLUSIONS

During extended multimodal NAT for PC, 22% of patients experienced a BAE. Although BAEs were not associated with a significant interruption of treatment, patients who experienced a BAE had worse OS.

CT imaging features of bile duct stent complications

Biliary stents have been widely used to treat both malignant and benign biliary obstruction. Biliary stenting serves as a temporary measure to maintain ductal patency and promote bile drainage. Biliary decompression can help relieve clinical symptoms of pain, obstructive jaundice, pruritis, fat malabsorption, and failure to thrive and prevent disease progression, such as secondary biliary cirrhosis and end-stage liver failure. Endoscopic placement of biliary endoprosthesis is a minimally invasive procedure well tolerated by most patients but is not without problems. Multiple early and late complications have been reported in the literature and Computed Tomography (CT) is the most used modality to assess normal positions and evaluate patients suspected of stent complications. The aim of this article is to provide a review various of biliary stent related complications, as seen on CT. Current literature on risk factors, diagnosis and management is also discussed.

Risk Factors Associated with Acute Pancreatitis after Percutaneous Biliary Intervention: We Do Not Know Nearly Enough

Percutaneous transhepatic cholangiodrainage (PTCD) and percutaneous transhepatic biliary stenting (PTBS) may be used as a palliative treatment for inoperable patients with malignant biliary obstruction (MBO) to improve the prognosis and their quality of life. However, acute pancreatitis is a common and severe complication that cannot be ignored after PTCD and PTBS in patients with MBO. A few cases may develop severe pancreatitis with a higher mortality rate. In this study, we summarize the known risk factors for acute pancreatitis after percutaneous biliary interventional procedures and investigate possible risk factors to reduce its occurrence by early identifying high-risk patients and taking appropriate measures.

The feasibility of percutaneous transhepatic gallbladder aspiration for acute cholecystitis after self-expandable metallic stent placement for malignant biliary obstruction: a 10-year retrospective analysis in a single center

BACKGROUND/AIMS

Patients with acute cholecystitis (AC) after metallic stent (MS) placement for malignant biliary obstruction (MBO) have a high surgical risk. We performed percutaneous transhepatic gallbladder aspiration (PTGBA) as the first treatment for AC. We aimed to identify the risk factors for AC after MS placement and the poor response factors of PTGBA.

METHODS

We enrolled 401 patients who underwent MS placement for MBO between April 2011 and March 2020. The incidence of AC was 10.7%. Of these 43 patients, 37 underwent PTGBA as the first treatment. The patients' responses to PTGBA were divided into good and poor response groups.

RESULTS

There were 20 patients in good response group and 17 patients in poor response group. Risk factors for cholecystitis after MS placement included cystic duct obstruction (p<0.001) and covered MS (p<0.001). Cystic duct obstruction (p=0.003) and uncovered MS (p=0.011) demonstrated significantly poor responses to PTGBA. Cystic duct obstruction is a risk factor for cholecystitis and poor response factor for PTGBA, whereas covered MS is a risk factor for cholecystitis and an uncovered MS is a poor response factor of PTGBA for cholecystitis.

CONCLUSION

The onset and poor response factors of AC after MS placement were different between covered and uncovered MS. PTGBA can be a viable option for AC after MS placement, especially in patients with covered MS.

Prevention of Serious Complications during Endoscopic Ultrasound-Guided Biliary Drainage: A Case-Based Technical Review

Endoscopic ultrasound-guided biliary drainage (EUS-BD) has a potential risk of clinically significant adverse events including fatal complications. Learning from complications improves the results from interventional procedures especially the high-risk procedure like EUS-BD. The various complications that have been reported following EUS-BD include bile leak, bleeding, cholangitis, peritonitis, stent migration both internal and external as well as in the peritoneal cavity and fatal perforations. In this technical review, we discuss technical strategies to prevent serious adverse events during EUS-BD using a case based approach.

Percutaneous cholecystostomy for acute cholecystitis after stent insertion in patients with malignant biliary obstruction: clinical outcomes of 107 patients

BACKGROUND

The outcome of percutaneous cholecystostomy (PC) in malignant patients with acute cholecystitis (AC) after biliary stent insertion has not been investigated in a large group.

PURPOSE

To evaluate the clinical outcomes of PC for AC after stent insertion in patients with malignant biliary obstruction.

MATERIAL AND METHODS

From April 2007 to February 2019, 107 patients (57 men, 52 women; mean age = 67.5 years; age range = 27-93 years) who had undergone PC for AC after biliary stent insertion were retrospectively evaluated. Of the 107 patients, 86 underwent biliary stent insertion by the endoscopic approach and the remaining 21 patients by the percutaneous approach. All patients were classified into three groups: those with stent-induced AC; those with cancer-induced AC; and those with AC without mechanical cause (biliary stent, GB stone, or cancer invasion). The mean survival time, recurrence rate, symptom improvement, and cystic duct patency in each patient group were analyzed.

RESULTS

Stent-induced AC (n = 40, 37.4%) developed with a mean onset time of six days (range = 0-14 days), AC without mechanical cause (n = 27, 25.2%), 87 days (range = 15-273 days), and cancer-induced AC (n = 40, 37.4%), 137 days (range = 15-447 days) after stent insertion. Symptom resolution and significant improvement in laboratory test values were achieved in 95 patients (88.8%) within four days after PC.

CONCLUSION

PC is a technically safe and effective method for the treatment of AC after biliary stent insertion in patients with malignant biliary obstruction.

Can the laser-cut covered self-expandable metallic stent be the first choice for patients with unresectable distal malignant biliary obstruction? (with video)

OBJECTIVES

To evaluate whether laser-cut covered self-expandable metallic stents (LC-CSEMSs) can be the first choice for patients with unresectable distal malignant biliary obstruction (DMBO).

METHODS

Patients with unresectable DMBO who received LC-CSEMS (September 2014-December 2020) or braided CSEMS (B-CSEMS) (July 2013-December 2020) placement for biliary drainage were enrolled. Outcomes, including endoscopic CSEMS removal, of LC-CSEMSs and B-CSEMSs were compared.

RESULTS

Overall, 124 patients received LC-CSEMSs placement, and 121 B-CSEMSs. Technical success, clinical success, and procedure-related adverse event rates with LC-CSEMSs were 100%, 96.8%, and 6.5%, respectively, and 100%, 95.9%, and 5.8%, respectively, for B-CSEMSs, with no significant difference (P > .99, .75, and >.99, respectively). The recurrent biliary obstruction (RBO) rates with LC-CSEMSs and B-CSEMSs were 9.7% (12/124) and 13.2% (16/121), respectively (P = .43). The median time to RBO with LC-CSEMSs and B-CSEMSs was 198 (interquartile range [IQR], 124-244) days and 191 (IQR, 106-271) days (P = .41). The endoscopic removal success rates of LC-CSEMSs and B-CSEMSs were 88.9% (8/9) and 90% (9/10) (P > .99), although there were a small number of cases.

CONCLUSIONS

The non-inferiority of LC-CSEMSs was proven. LC-CSEMSs can be considered as the first choice for patients with unresectable DMBO.

Dilated main pancreatic duct can be a negative predictor of pancreatitis related to biliary SEMS insertion across the papilla

OBJECTIVES

Post-ERCP pancreatitis (PEP) after self-expandable metallic stent (SEMS) insertion across the papilla of Vater is an important adverse event that affects the patient's quality of life (QOL). We examined the predictive factors of PEP after SEMS insertion to treat obstructive jaundice due to malignancy.

METHODS

Ninety patients who underwent biliary SEMS insertion for biliary obstruction due to malignancy at Iwata City Hospital between 2010 and 2018 were reviewed. We evaluated the relationship between the incidence of PEP after biliary SEMS insertion and clinical factors. We measured the thickness of the pancreatic parenchyma and diameter of the main pancreatic duct (MPD) at the left side of the corpus vertebrae.

RESULTS

Mild and severe PEP were diagnosed in 10 (11.1%) and 1 (1.1%) patients, respectively. Only the thickness of the pancreatic parenchyma and diameter of MPD significantly differed between the PEP and non-PEP groups. The incidence of PEP among patients whose thickness of the pancreatic parenchyma at the left side of the corpus vertebrae was less than 9.5 mm (0%) on computed tomography was lower than that in patients whose thickness was 9.5 mm or greater (34.4%). Similarly, a wider (5 mm or more) diameter of MPD (4.3%) reduced the incidence of PEP compared with a narrower diameter (40.0%). Logistic regression analysis revealed that the probability of PEP decreases 3.91 times for every 1-mm increase in MPD diameter (95% CI 1.23-12.4, p = .02).

CONCLUSION

Based on our study, a dilated MPD is a negative predictive factor of pancreatitis related to biliary SEMS insertion.

Influence of fully covered metal stenting on the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis: A large multicenter study·

BACKGROUND AND AIM

Fully covered self-expandable metal stents (FCSEMSs) have been increasingly used in the management of benign or malignant biliary disorders. However, the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) with transpapillary placement of the FCSEMS remains controversial. This study therefore aimed to investigate the risk of PEP in patients who received FCSEMS implantation.

METHODS

In total, 602 patients who underwent endoscopic transpapillary FCSEMS placement at five Chinese medical centers, between 2011 and 2018, were included in this retrospective study. Patients who were younger than 18 years and with stent placement above the papilla were excluded from the study. PEP and the risk factors were reviewed.

RESULTS

PEP occurred in 56 (9.3%) patients, and eight (1.3%) of them experienced moderate-to-severe PEP. The incidence of PEP rose to 14.6% (51/349) when patients had no pancreatic duct (PD) dilation, and even to 18.6% if no prophylactic approaches were adopted. Prophylactic PD stenting showed better efficacy in reducing the incidence of PEP than did rectal use of indomethacin (3.5% vs 10.8%, P = 0.023). Multivariate logistic regression revealed that difficult cannulation (OR 2.837, 95% CI 1.245-6.465, P = 0.013), PD dilation (OR 0.145, 95% CI 0.05-0.422, P < 0.001), and PD stenting (OR 0.247, 95% CI 0.089-0.686, P = 0.007) were significantly associated with PEP risk. Post-procedure cholecystitis was found in 4.0% of patients.

CONCLUSION

The risk of post-procedure pancreatitis is modestly increased in patients receiving transpapillary FCSEMS placement, particularly when there is absence of PD dilation. Thus, prophylactic pancreatic stenting is recommended in such a condition.

Cholecystitis after Placement of Covered Self-Expandable Metallic Stents in Patients with Distal Malignant Biliary Obstructions

Background/Aims

Cholecystitis can occur after the placement of covered self-expandable metallic stents for distal malignant biliary obstructions. We aimed to identify risk factors for cholecystitis following covered self-expandable metallic stent placement.

Methods

We investigated risk factors related to cholecystitis following covered self-expandable metallic stent placement in 118 patients with distal malignant biliary obstructions between January 1, 2015 and April 30, 2019. Endoscopic assessments and tumor invasion to the arteries feeding the gallbladder were determined by a pancreaticobiliary endoscopist and a radiologist, respectively.

Results

The median patient age was 72 years (men, 61.0%). The flow of the contrast agent into the gallbladder and tumor involvement in the orifice of the cystic duct were observed in 35 (29.7%) and 35 (29.7%) patients, respectively. During the observation period (median, 179 days), cholecystitis occurred in 18 (15.3%) patients. Multivariate analysis revealed the flow of the contrast agent into the gallbladder (p=0.023) and tumor involvement in the orifice of the cystic duct (p=0.005) as significant independent risk factors associated with cholecystitis.

Conclusions

The flow of the contrast agent into the gallbladder and tumor involvement in the orifice of the cystic duct are potential independent risk factors for cholecystitis following the placement of covered self-expandable metallic stents. A follow-up prospective study is warranted to validate their influence.