Intestinal metastases diffused from primary gastric adenocarcinoma with signet ring cells: case report
Haiping Qi1, Weiyan Li1, Xingting Luo1
1Department of Gastroenterology, The First Affiliated Hospital of Guilin Medical University, Guilin, China.
None:
Signet ring cell carcinoma (SRCC), a poorly differentiated subtype of gastric adenocarcinoma, is known for its high metastatic capacity. However, metastases to the intestines, both small and large, are uncommon. This report describes a unique case of gastric adenocarcinoma with signet ring cells features and multiple polypoid intestinal metastases.
Case Presentation:
A 62-year-old man with primary gastric SRCC exhibited epigastric pain, lower abdominal distension, and a significantly elevated serum CEA level (400 ng/ml). Endoscopic evaluations detected numerous ulcerative and polypoid growths in the stomach, duodenum, distal ileum, ileocecal valve, and colorectum. Imaging studies confirmed thickening of the gastric wall, abdominal lymph node enlargement, and multiple bone metastases. Examination of tissue samples using histopathological and immunohistochemical methods indicated poorly differentiated adenocarcinoma with signet ring cell features, confirming the intestinal lesions as metastases of gastric SRCC.
Conclusion:
In this report, we describe a rare instance of gastric adenocarcinoma characterized by signet ring cells and multiple intestinal polypoid metastases. Differentiating between metastatic gastric signet ring cell carcinoma (SRCC) and primary colorectal carcinoma can be aided by assessing CK7 and CK20 expression, where CK7+/CK20+ is more frequently observed in gastric adenocarcinomas. The precise mechanism underlying this distinctive metastatic pattern remains uncertain, although peritoneal seeding has been proposed as a potential route. Treatment protocols for such cases are not standardized; typically, systemic chemotherapy is favored over surgical intervention for widespread lesions, and the prognosis is generally unfavorable. This case underscores the unusual metastatic patterns of gastric SRCC, emphasizing the importance of thorough endoscopic and pathological assessments to prevent misdiagnosis and offering clinical guidance for managing uncommon metastases in gastric cancer.
