Next-generation sequencing of bile cell-free DNA for the early detection of patients with malignant biliary strictures.

OBJECTIVE: Despite significant progresses in imaging and pathological evaluation, early differentiation between benign and malignant biliary strictures remains challenging. Endoscopic retrograde cholangiopancreatography (ERCP) is used to investigate biliary strictures, enabling the collection of bile. We tested the diagnostic potential of next-generation sequencing (NGS) mutational analysis of bile cell-free DNA (cfDNA). DESIGN: A prospective cohort of patients with suspicious biliary strictures (n=68) was studied. The performance of initial pathological diagnosis was compared with that of the mutational analysis of bile cfDNA collected at the time of first ERCP using an NGS panel open to clinical laboratory implementation, the Oncomine Pan-Cancer Cell-Free assay. RESULTS: An initial pathological diagnosis classified these strictures as of benign (n=26), indeterminate (n=9) or malignant (n=33) origin. Sensitivity and specificity of this diagnosis were 60% and 100%, respectively, as on follow-up 14 of the 26 and eight of the nine initially benign or indeterminate strictures resulted malignant. Sensitivity and specificity for malignancy of our NGS assay, herein named Bilemut, were 96.4% and 69.2%, respectively. Importantly, one of the four Bilemut false positives developed pancreatic cancer after extended follow-up. Remarkably, the sensitivity for malignancy of Bilemut was 100% in patients with an initial diagnosis of benign or indeterminate strictures. Analysis of 30 paired bile and tissue samples also demonstrated the superior performance of Bilemut. CONCLUSION: Implementation of Bilemut at the initial diagnostic stage for biliary strictures can significantly improve detection of malignancy, reduce delays in the clinical management of patients and assist in selecting patients for targeted therapies.

Gallbladder perforation after closed thoracoabdominal trauma, diagnosed and treated by ERCP.

Single gallbladder injury after abdominal trauma is a rare finding. Early diagnosis of this disease is often difficult due to the variability of symptoms and unspecific results in the usual radiological tests. The usual management in patients with vesical trauma is surgery. We report a case of a patient with a gallbladder perforation after closed thoracoabdominal trauma diagnosed and treated with ERCP and a conservative management with good clinical evolution.

Prospective observational study of the incidental findings on endoscopic ultrasonography: should a complete exploration always be performed?

OBJECTIVES: To quantify the additional non-suspected new diagnoses made on upper endosonography (EUS) which were unknown before the procedure, and to analyse their influence on the management of patients. A further objective was to evaluate the influence that previous radiological or endoscopic explorations have on the capacity of EUS to diagnose these unsuspected lesions. MATERIAL AND METHODS: During a 2-year period every patient sent to our unit for upper EUS underwent a complete investigation, after signing an informed consent document. An upper EUS was considered as complete whenever the gut wall, pancreas, biliary tract, ampulla, large abdominal vessels, liver, spleen, left adrenal gland, posterior mediastinum and thyroid lobes had been explored. An additional diagnosis (AD) was defined as a diagnosis made on EUS that was previously unknown and not suspected. A significant additional diagnosis (SAD) was defined as an AD that required further study. The results of complementary explorations carried out before EUS were registered. RESULTS: A total of 239 patients were included in the study. ADs were found in 92 patients (38.5%), which were considered to be SADs in 27 patients (11.3%). Those patients had previously undergone computed tomography (CT) and those who underwent more than one exploration had fewer incidences of ADs on EUS (p=0.03 and p=0.02, respectively). No exploration alone or in combination with others showed any influence on the capacity of EUS to find a SAD (p >0.05). CONCLUSIONS: In our series, an AD was found on upper endosonography in 38.5% of the patients studied, and a SAD in 11.3%. The probability of finding a SAD on EUS is not influenced by previous endoscopic or radiologic explorations.

Advances in the endoscopic management of pancreatic collections.

Treatment of pancreatic collections has experienced great progress in recent years with the emergence of alternative minimally invasive techniques comparing to the classic surgical treatment. Such techniques have been shown to improve outcomes of morbidity vs surgical treatment. The recent emergence of endoscopic drainage is noteworthy. The advent of endoscopic ultrasonography has been crucial for treatment of these specific lesions. They can be characterized, their relationships with neighboring structures can be evaluated and the drainage guided by this technique has been clearly improved compared with the conventional endoscopic drainage. Computed tomography is the technique of choice to characterize the recently published new classification of pancreatic collections. For this reason, the radiologist's role establishing and classifying in a rigorously manner the collections according to the new nomenclature is essential to making therapeutic decisions. Ideal scenario for comprehensive treatment of these collections would be those centers with endoscopic ultrasound and interventional radiology expertise together with hepatobiliopancreatic surgery. This review describes the different types of pancreatic collections: acute peripancreatic fluid collection, pancreatic pseudocysts, acute necrotic collection and walled-off necrosis; the indications and the contraindications for endoscopic drainage, the drainage technique and their outcomes. The integrated management of pancreatic collections according to their type and evolution time is discussed.