A Novel Endoscopic Technique to Diagnose Gastric Cancer in the Excluded Stomach After Roux-en-Y Gastric Bypass

Abstract

Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed weight reduction surgeries. Evaluation of diseases of the excluded stomach (Figure 1) such as ulcers or malignancy pose a significant challenge due to difficulty in accessing the excluded portion of the stomach. We report the first case of the gastric cancer of the excluded stomach diagnosed with endoscopic ultrasound (EUS). A 50-year-old female with Roux-en-Y gastric bypass surgery performed six years ago presented with epigastric pain, nausea and recurrent gastrointestinal bleeding for nine months. Multiple upper and lower gastrointestinal (GI) endoscopies, as well as a video capsule endoscopy failed to identify the source of her recurrent bleeding. Abdominal computed tomography (CT) scan showed a mass in the excluded stomach with enlarged lymph nodes in the perigastric region and gastrohepatic ligament. An EUS via gastric pouch showed diffuse wall thickening of the excluded stomach at the antrum (Figure 2) and two enlarged lymph nodes in the gastrohepatic ligament. Fine needle aspiration (FNA) of the lymph nodes and the gastric wall of the excluded stomach revealed poorly differentiated gastric adenocarcinoma (Figure 3). The biopsy was negative for H. pylori infection. Staging laparoscopy confirmed peritoneal implants. Gastric cancer is the fifth most common malignancy worldwide and fourth leading cause of cancer-related deaths. RYGB is associated with a 4-fold reduction in the incidence of gastric cancer in animal models. Tinoco et al reported the incidence of gastric cancer in the excluded stomach to be 0.03% among 3047 patients who underwent bariatric surgery. However, larger prospective studies are lacking regarding the incidence of cancer in this population. Risk factors for gastric cancer include H. pylori infection, smoking, high-salt intake, family history of stomach cancer, obesity and a diet low in fruits and vegetables. Symptoms are non-specific and include anorexia, epigastric pain, anemia and weight loss following a period of stability or weight gain. Minimal invasive techniques which can be used to evaluate the excluded stomach are double balloon enteroscopy (DBE), percutaneous endoscopy, virtual gastroduodenoscopy, laparoscopic transgastric endoscopy and EUS. Patients with prior RYGB presenting with alarming, new onset, unexplained symptoms should prompt evaluation including adequate visualization of the excluded stomach with imaging and advanced endoscopic techniques.Figure: showing postoperative anatomy of modern RYGB.Figure: EUS showing antral wall thickening in the excluded stomach (arrow).Figure: Histology slide showing poorly differentiated adenocarcinoma.