Gastric Lymphomas and Other Gastric Malignancies
On endoscopy, gastric lymphomas present polypoid mass, ulcerative infiltration, or hypertrophic thick folds. At times, however, the features are nonspecific with mucosal hyperemia or irregular erosions. Tumor stage as well as histologic subtypes, which are the most important prognostic and therapeutic factors, should be determined by endoscopic procedures.
Gastric carcinoids can be classified by histologic grade and clinical conditions. Type I and II tumors present multiple, small, localized polyps associated with hypergastrinemia, either secondary to chronic atrophic gastritis or as part of Zollinger-Ellison syndrome, and have low malignant potential. By contrast, large solitary (type 3) and poorly differentiated carcinomas (type 4) are not associated with hypergastrinemia and commonly metastasize.
Rarely, metastatic tumors to the stomach are found in melanoma and lung and breast cancers. Polypoid masses mimicking submucosal tumors are common endoscopic features.
KeywordsGastric lymphoma Gastric carcinoid Metastatic tumor