Endocrine Abstracts

We report a case of GIST comorbidity with pituitary macroadenoma presenting with gastrointestinal bleeding.

Case: A 56-year-old male patient was admitted to the emergency department with complaints of hematemesis. Antral gastritis and a mass about 3 cm in diameter with irregular margins in the ampulla detected in upper gastrointestinal endoscopy. Irregular, heterogeneous, hypoechoic solid mass lesion, ~ 36×48 mm in size, was observed inferior–lateral neighborhood of the pancreas in the upper abdomen ultrasonography. Solid mass lesion ~ 4 cm in diameter was observed under the head of the pancreas slightly distorting the duodenal ans detected in abdomen tomography. Whipple procedure, pancreatic resection and cholecystectomy was performed to the patient with an initial diagnosis of pancreatic tumor. Postoperative histopathology was reported as gastrointestinal stromal tumor. Stainning with CD117, CD34, and actin was detected while there was no staining with S100, desmin, CD99, and CD138. Proliferative index was around 1–2% with Ki-67. Hypoglycemia and hyponatremia was developed postoperatively. Insulin and C-peptide levels were normal during hypoglycemia. All of the anterior pituitary hormones were low. L-thyroxine therapy was started after steroid replacement. Dextrose and isotonic NaCl replacement was performed. In the follow-up hypoglycemia and hyponatremia was improved. Sella was larger than normal in pituitary MR. Lobulated mass (pituitary adenoma?), was detected in sella, with size of 28×26×24 mm, showing heterogeneous staining with contrast material, compressing optic chiasm and bilateral optic nevre, and causing lateral cavernous sinus invasion. Nonfunctional pituitary adenoma pituitary was detected as a result of the operation.

Result: GISTs are a rare type of gastrointestinal tumours that are most commonly located in the small bowel or stomach but can also be found in the duodenum. Gastrointestinal stromal tumors may be associated with pituitary adenomas. This issue must not be ignored and has to be examined in this respect.