S3715 A Leather Bottle Stomach: Rare Case of Gastric Adenocarcinoma With Signet Cell Features

Introduction: Gastric cancer is one of the most common cancers worldwide - and was previously the leader of cancer related mortality until the 1980’s. With advancements in discovery of etiologies, namely the detection of H. Pylori - incidence of gastric cancer has declined over the past decades. A common finding on imaging is the diffuse gastric wall thickening - the “leather water bottle” or Linitis Plastica. A representation of diffuse infiltration of the cancer into the wall of a hollow organ, in this case - the stomach, giving it’s rugged and preserved structural shape. We present a case of poorly differentiated gastric adenocarcinoma with signet ring cell features in setting of portal hypertensive gastropathy. Case Description/Methods: 70-year-old female with PMH of HCV (treated with SVR) and 20 pack year tobacco history presented with complaints of weight loss, decreased appetite and early satiety with no other complaints for one month. Physical exam significant for bi-temporal wasting otherwise unremarkable. Initial chemistries within normal limits. CT abdomen and pelvis revealing a prominent thickening of the wall of the stomach as well as inhomogeneous soft tissue attenuation in the omentum concerning for neoplastic disease. EGD showed evidence of portal hypertensive gastropathy with distal gastric body thickening in addition to the examined duodenum revealing duodenitis. Biopsies of the stomach revealed poorly differentiated adenocarcinoma with signet ring cell features while the duodenal mucosa was negative for significant histopathologic abnormality. H. pylori immunostain was negative. Insufficient tissue for HER2 and PDL-1 assessment. Oncology evaluation included PET CT with significant circumferential thickening and hypermetabolic activity of the stomach with additional focus of modular hypermetabolic activity at pyloric and duodenal 2nd portion suggestive of multi centric disease. Diffuse omental modularity and ascites at low level metabolic activity consistent with omental metastasis and malignant ascites. Discussion: While our patient presented late in the disease course, there are still available palliative chemotherapy opportunities. Advances have been made in molecular identification and subtypes within the gastric cancer umbrella for more targeted therapy. Recent FDA approval (April 2021) of the addition of Opdivo (immunotherapy) to FOLFOX (chemotherapy) for treatment of metastatic gastric cancer has allowed our patient to receive the most up to date treatment option.Figure 1.: Figures 1-A through C are endoscopic images of the gastric body (evidence of portal hypertensive gastropathy), the duodenal bulb (suggesting duodenitis) and the 2nd portion of the duodenum. Figure 1-D is a CT Abdomen-Pelvis with Contrast depicting the classic radiographic finding of gastric cancer - 'linitis plastica' with surrounding peri-gastric lymphadenopathy. Figures 1-E and F are NM PET scan's with evidence of diffuse hypermetabolic activity in the stomach wall with uptake of SUV max 10.1 in addition to the 2nd portion of the duodenum with uptake of SUV max 5.7 - suggestive of multi-centric disease.