Abdominal pain, diabetes mellitus and an absent piece of pancreas

A 55 years non-alcoholic gentleman was admitted through emergency medical services with sudden severe upper abdominal pain in the epigastrium with radiation to back. The pain in the upper abdomen was associated with recurrent bouts of bilious vomiting. He denied history for any other gastrointestinal symptoms. He is a known diabetic since last 3 years requiring insulin and oral hypoglycaemic agents. He has had similar episode of pain six months ago which was managed conservatively elsewhere. He was clinically stable with tenderness in the epigastrium.