Endoscopic retrograde cholangiopancreatography and endoscopic ultrasound are increasingly being used to manage complex disease of the bile duct, pancreas and cancer. Gastroenterology patients at the Los Angeles County Hospital presents a unique and diverse patient population.

Our aim is to study the biochemical, radiographic, and clinical predictors of bile duct stones. Exploratory aims include the study of the management of cholangitis, bile leaks, GI cancer diagnosis and management, and the management of pancreaticobiliary problems in the underserved.

All patients managed by EUS or ERCP at the LA County & USC University Hospitals will be enrolled in the databaseThe timing, clinical presentation, and objective details of patient presentation are recorded prospectively. Additionally the results of the subsequent ERCP and EUS procedures. Subsequent, clinical course and pathology will also be recorded.

AIMS A) Characterize unusual disease and pathologic presentations which require endoscopic treatment in a large safety net hospital B) To study the impact of EUS and ERCP on the management of these patients. C) Analyze how EUS and ERCP results correlate with other radiographic methods including conventional ultrasound and computed tomography (CT) D) Compare role of EUS and ERCP in a safety net versus tertiary care center

II) BACKGROUND Endscopic Ultrasound (EUS) which consists of an endoscope containing a high frequency transducer, has become standard of care to evaluate gastrointestinal cancer as well as diseases included chronic pancreatitis. EUS with fine needle aspiration (FNA) has been demonstrated to be the least invasive and most effective means to acquire tissue in a number of situations included pancreas cancer and maligant lymph nodes. Endoscopic Retrograde Cholangiopancreatography (ERCP) is a therapeutic procedure used to manage choledocholithiasis, bile duct obstruction and occasional pancreatic ductal problems. Its diagostic uses are now more limited with the advent of EUS and cross sectional radiographic studies including CT and magnetic resonance cholangiopancreatography (MRCP).

A number of leading ERCP/EUS groups including those at the University of Alabama (Birmingham, Alabama), the Cleveland Clinic (Cleveland Ohio) and the Mayo Clinic (Rochester, Minnesota) have developed ERCP/EUS databases which have led to important insight about the role of these procedure and the diseases they are used to manage. However, these groups and indeed almost the entire world literature regarding EUS and ERCP focuses on America, Western European, and Japanese populations.

The goal of this database will be to study the impact of EUS and ERCP on an underserved population at LAC. The prevalence of certain diseases including cholangitis, large bile duct stones, and gastric cancer are markedly higher at our institution than in other western facilities presenting a unique opportunity to report how they are treated as part of standard management.

IIIA) DESIGN AND METHODOLOGY

1. ALL PROCEDURES ARE DONE STRICTLY AS STANDARD OF CARE.
2. Detailed collection sheets containing no PHI but with detailed information about laboratories, symptoms, radiographic tests, time of presentation and procedure detals are prospectively completed for patients undergoing EUS or ERCP by the Gastroenterology service at the USC Hospitals. The resulting pathology and clinical course are collected on these anonymized forms.
3. The information in the extraction sheets is entered into a database stripped of all personal health identifiers.

IIIB) PLANNED DATA COLLECTION

1. The aim of this project will be to develop a prospective database of EUS/ERCP cases at USC.
2. For both ERCP and EUS cases detailed information regarding the presentation of the patients will be noted. Specifically, which radiographic and biochemical markers and clinical symptoms are of interest.

4) For EUS the outcomes include the confirmation by biopsies and imaging of the underlying pathology.

5) For ERCP the outcomes are procedural success and more specifically bile duct stone confirmation and removal, treatment of cholangitis, treatment of leaks biliary, and decompression of obstruction. Success of anesthesia strategy is an aim of the collection.

6) For potential quality of care assessment procedure complications and success of anesthesia strategy are a priori areas of study

IV) STATISTICAL CONSIDERATIONS As this study involves creation of a database of standard of care management of patients by EUS and ERCP primarily descriptive statistics will be used in future studies. If individual groups are compared (ie those with positive versus atypical fine needle aspiration) chi squared versus t statistic will be used for analysis depending on distribution..

Inclusion Criteria:

• All patients undergoing EUS or ERCP at LAC, UH, and Norris Cancer Hospitals as standard of clinical care will be enrolled.

Exclusion Criteria:

• None of the patients will be excluded.

All patients undergoing ERCP or EUS for clinical indications