S2108 Metastatic Gastric Carcinoma Masquerading as a Pedunculated Bleeding Gastric Polyp

Abstract

INTRODUCTION: The majority of gastric polyps are found incidentally and are benign hyperplastic or fundic gland polyps with low malignant potential. Up to 10% can be adenomas which possess a higher neoplastic potential. Appropriate management of gastric polyps is vital as some may harbor underlying malignancy or cause complications, e.g. bleeding. We present a case of an elderly patient with acute upper GI bleeding from a metastatic gastric adenocarcinoma masquerading as a typical fundic gland polyp. CASE DESCRIPTION/METHODS: A 77-year-old woman presented with 2 days of loose foul-smelling black stools and fatigue, was hemodynamically stable with a benign abdominal exam, and had a hemoglobin of 7.1 g/dL. EGD revealed a 3.5 × 2.0 × 1.8cm pedunculated polyp on the lesser curvature of the stomach with large adherent clot, which was removed and hemostasis achieved (figures A/B). Histopathology showed a gastric tubular adenoma with intra-mucosal carcinoma and invasion into the lamina propria. Staging scans revealed peritoneal implants consistent with disseminated stage IV disease. Due to age, a palliative treatment approach was taken with radiotherapy. DISCUSSION: Gastric polyps can be seen in incidentally on 6% of endoscopies with gastric adenomas representing only 6–10%. While all classes of gastric polyps are usually incidental findings on EGD, gastric adenomas are more likely than all other classes to cause complications. The neoplastic potential of two other commonly encountered polys - hyperplastic and fundic gland polys - are generally quite low at 1% and virtually nonexistent outside of familial polyposis syndromes, respectively. On the contrary, gastric adenomatous polyps are associated with concurrent gastric carcinoma in 8–59% of cases. Isolated polyps that are pedunculated with normal surrounding mucosal tissue, as seen here, conventionally have a low suspicion for malignancy. Furthermore, is it uncommon to encounter a purely pedunculated gastric adenoma, as the majority of these lesions are sessile. Often, signs of upper GI bleeds can be the initial presentation of gastric carcinomas. As older populations are more prone to gastric polyps, many may also have comorbidities such as chronic anemia or on medications preventing hemostasis, which has potential to be detrimental. In conclusion, here we highlight a unique presentation of metastatic gastric carcinoma and stress vigilant assessment of all gastric polyps and discuss potential complications as even benign appearing lesions could harbor malignancy.Figure 1.: 3.5 × 2 × 1.8 cm pedunculated polyp seen on retro-flexion on the lesser curvature of the gastric body with an adherent clot with normal appearing surrounding gastric mucosa.Figure 2.: Site after local epinephrine injection and hot-snare polypectomy, prior to hemostatic clip placement.