Probe-Based Confocal Endomicroscopy in Primary Sclerosing Cholangitis: Not All Inflammatory Strictures Are the Same

Individual probe based confocal laser endomicroscopy criteria in the analysis of indeterminate biliary strictures

OBJECTIVES

Evaluation of indeterminate biliary strictures remains challenging due to limited sensitivity of endoscopic tissue sampling. Biliary probe-based confocal laser endomicroscopy (pCLE) has shown promise to detect and exclude neoplasia. However, knowledge of whether individual inflammatory criteria are more prevalent in neoplasia compared to benign strictures is limited. The objective of this work is to improve diagnosis of neoplastic and inflammatory conditions using pCLE.

MATERIALS AND METHODS

The charts of all patients who underwent pCLE at a single referral center between 2009 and 2015 were reviewed. ERCP reports were reviewed for eleven Miami and Paris criteria. Primary outcome was the identification of neoplasia by histopathology (defined as high-grade dysplasia and/or adenocarcinoma). To model predictors of neoplasia, we fit a binary regression model incorporating data from pCLE operating criteria, pCLE impression, and PSC status.

RESULTS

97 patients were identified. In the 27 patients with neoplasia, there was increasing number of Miami malignant criteria (Pearson r = 0.512, p < .001) while inflammatory criteria were less prevalent. 10% (5/51, p < .001) of patients with benign pCLE impression developed neoplasia, while 48% (22/46, p < .001) with suspicious pCLE impressions developed neoplasia. The binary regression model to predict neoplasia had a sensitivity of 83.3%, specificity of 92.5%, and overall accuracy 89.7%.

CONCLUSIONS

Presence of malignant criteria and absence of certain inflammatory criteria are more prevalent in patients with neoplasia. Our model, which weights individual imaging components, shows impressive sensitivity and specificity over prior prognostic efforts. Prospective studies will be required to evaluate this model.

Endoscopic management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare but clinically important cholestatic liver disease. Histopathologically and cholangiographically, PSC is characterized by intra- and/or extra-hepatic bile duct inflammation and fibro-obliteration, which ultimately leads to biliary cirrhosis and related sequelae, including development of hepatobiliary and colorectal carcinomata. PSC can be diagnosed at essentially any age and carries a median survival of 15-20 years, regardless of age at diagnosis, and is a foremost risk factor for cholangiocarcinoma. Given the chronic and progressive nature of PSC, its inherent association with both neoplastic and non-neoplastic biliary tract complications, and the lack of effective pharmacotherapies, alimentary and biliary tract endoscopy plays a major role in the care of patients with PSC. Areas covered: Here, we provide a narrative review on endoscopic management of PSC, including established and evolving applications to the diagnosis and treatment of both its benign and malignant complications. Expert commentary: Due to the rarity of PSC and the considerable patient-years required to rigorously study major endpoints, there remains a paucity of high-quality evidence regarding its management. As the advanced endoscopic repertoire expands, so has the interest in developing best practices in PSC, which we discuss herein.

Endoscopic Management of Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) remains a rare but potentially devastating chronic, cholestatic liver disease. PSC causes obstruction of intra- and/or extra-hepatic bile ducts by inflammation and fibrosis, leading to biliary obstruction, cirrhosis and portal hypertension with all associated sequelae. The most dreaded consequence of PSC is cholangiocarcinoma, occurring in 10-20% of patients with PSC, and with population-based estimates of a 398-fold increased risk of cholangiocarcinoma in patients with PSC compared to the general population. We use the 4-D approach to endoscopic evaluation and management of PSC based on currently available evidence. After laboratory testing with liver chemistries and high-quality cross-sectional imaging with MRCP, the first D is Dominant stricture diagnosis and evaluation. Second, Dilation of strictures found during ERCP is performed using balloon dilation to as many segments as possible. Third, Dysplasia and cholangiocarcinoma diagnosis is performed by separated brushings for conventional cytology and fluorescence in situ hybridization (FISH), and consideration for direct cholangioscopy with SpyGlass™. Fourt and finally, Dosing of antibiotics is critical to prevent peri-procedural cholangitis. The aim of this review article is to explore endoscopic tools and techniques for the diagnosis and management of PSC and provide a practical approach for clinicians.

Is Seeing Really Believing? Probe-based Confocal Laser Endomicroscopy in the Evaluation of Pancreaticobiliary Disease

Confocal laser endomicroscopy for real-time diagnosis during endoscopic procedures has now been in the mainstream clinical arena for a decade. Indeterminate biliary strictures and pancreatic cysts remain 2 difficult diagnostic challenges for the gastroenterologist, and the role this technology will play in the approach to these problems is still evolving. There is now a body of literature to guide the endoscopist in the use of this imaging tool, including how it may be useful in excluding biliary malignancy, and how miniaturization has allowed for endoscopic ultrasound-guided application of the probe within cysts. Interobserver variability remains a weakness of the system. Tips for use of this tool and interpretation of the imaging data it provides are discussed.