S3028 Swept Under the Adipose Rug: Is Bariatric Surgery a Risk Factor in the Development of Cancer?

Abstract

INTRODUCTION: According to the WHO, gastric cancer (95% of the cases are adenocarcinomas) is the third most common cause of cancer-related death and the fifth most common malignancy in the world today and can arise from any viable gastric mucosa. The Roux-en-Y gastric bypass is a commonly performed weight loss surgery that involves the creation of a small gastric pouch which is connected to the small intestine. We submit a case of gastric adenocarcinoma in the excluded gastric pouch of a prior Roux-en-Y bypass presenting with non-specific symptoms. CASE DESCRIPTION/METHODS: A 70 year old female with a past medical history of Roux-en-Y 15 years prior and subsequent gastroesophageal reflux disease presented to ER with greater than 2 months of intermittent epigastric pain. She had emesis and an inability to tolerate oral intake. Endoscopy was largely unremarkable and surgical pathology was negative. An esophagram showed nutcracker esophagus so the patient was started on Diltiazem. Continued symptoms prompted a CT abdomen showing relatively pronounced dilatation of the excluded stomach pouch with oral contrast material, likely entering via a fistula. Failure of conservative management prompted an exploratory laparotomy that revealed a severely distended stomach pouch, with intraoperative drainage of 800 cc of fluid. A tight duodenal stenosis with complete obstruction of the gastric outlet was also noted. Surgical pathology showed high grade adenocarcinoma involving the resected stomach and proximal duodenum with clear proximal and distal margins. H. pylori was not found. The tumor itself was positive for CK7 and CA 19-9 and negative for CK20. The tumor cells were ER/PR negative and cdx-2 negative. Repeat CT showed postsurgical changes without evidence of fluid collections or bowel obstruction. DISCUSSION: Up to 36% of patients who undergo gastric bypass are found to have duodenal reflux. Exposure to bile salts from the duodenal reflux can cause gastritis, intestinal metaplasia, and adenocarcinoma in the gastric mucosa. Literature review reveals multiple cases of gastric cancer in the excluded portion of the stomach after bariatric surgery, but long-term studies do not demonstrate a statistical or causal link between bariatric surgery and the development of gastric adenocarcinoma. Our case demonstrates that the excluded pouch of a Roux-en-Y bypass should be evaluated in at risk patients, even with non-specific symptoms, to allow early diagnosis of possible gastric adenocarcinomas.