What is the most likely diagnosis in a patient with a pancreatic mass and symptoms suggestive of Zollinger-Ellison syndrome?

In a patient with a pancreatic mass and symptoms suggestive of Zollinger-Ellison syndrome, the most likely diagnosis is gastrinoma. Zollinger-Ellison syndrome is characterized by the presence of gastrin-secreting tumors, known as gastrinomas, primarily located in the pancreas or duodenum. These tumors lead to excessive gastric acid production, resulting in severe gastric ulcers and diarrhea.

The presence of a pancreatic mass, in conjunction with the clinical features associated with Zollinger-Ellison syndrome—such as recurrent peptic ulcers, abdominal pain, and diarrhea—strongly points toward the diagnosis of gastrinoma. The tumors can be difficult to identify, but they typically manifest with the overproduction of gastrin, which can be confirmed through serum gastrin levels testing.

Other conditions listed do not align with the presentation or the pathophysiology associated with Zollinger-Ellison syndrome. While diabetic and alcoholic ketoacidosis relate to metabolic disturbances typically associated with diabetes and alcohol consumption, respectively, they do not involve pancreatic masses or gastrin production. Renal tubular acidosis is a disorder of the kidneys affecting acid-base balance, which is unrelated to the gastrointestinal symptoms and pancreatic involvement seen in the case of a gastrinoma. Thus, the specific