Mucinous cystadenocarcinoma of pancreas mimicking gastrointestinal stromal tumor of stomach: Case report

INTRODUCTION: Pancreatic mucinous cysadenocarcinoma is a rare neoplasm of pancreas which rarely presents as upper gastrointestinal bleed. CASE REPORT: A 45-year-old woman presented with history of repeated episodes of melena and abdominal pain. Upper gastrointestinal endoscopy revealed a growth in the body of the stomach likely to be a gastrointestinal stromal tumor (GIST). Endoscopic biopsy was inconclusive for GIST or malignancy. Computed tomography scan of the abdomen showed a well-defined multiloculated cystic lesion (11.8 × 11.1 × 6.4 cm) in the body and tail of the pancreas with involvement of the stomach. Preoperative diagnosis was a cystic neoplasm of the pancreas with tumor ingrowth into the stomach. The patient underwent enbloc resection of the stomach with distal pancreatectomy and splenectomy. Histopathological examination revealed low grade mucinous cystadenocarcinoma of the pancreas. DISCUSSION: Upper gastrointestinal bleed as a manifestation of cystic neoplasms of pancreas are rarely reported. Although some cases of hemoperitoneum were reported due to rupture of tumor; luminal gastrointestinal bleed is even rarer. It may be due to involvement of porto-mesenteric axis with portal hypertension, direct invasion of the gastric wall with ulceration of the gastric mucosa, communication between the tumor and the main pancreatic duct, and from the infiltrating tumor. CONCLUSION: Our case highlights the fact that mucinous cystadenocarcinoma of pancreas rarely can present with upper gastrointestinal hemorrhage, Moreover, if it is large enough to compress or invade the stomach, endoscopy may misdiagnose it as GIST.