MS-1435

A 58-year-old male patient visits the gastroenterology clinic complaining of weight loss and frequent loose, greasy stool for the past 6 months. He has a history of heavy alcohol use and has been admitted to the hospital multiple times for acute pancreatitis. Upon examination, the patient appears malnourished, and there is mild tenderness in the epigastric region. What hormone is likely to be significant in the investigation of his symptoms?