Inclusion Criteria:  Age 18 or older Willing to provide informed consent Biopsy proven gastric cancer, undergoing curative-intent gastrectomy No distant metastases Pathologic diagnosis of gastric adenocarcinoma Pre-treatment endoscopic measurement of less than or equal to 4 cm in diameter of the gastric cancer  Exclusion Criteria:  Contraindications to surgery +/- adjuvant therapy Allergy or intolerance to iron oxide compounds Allergy or intolerance to iodides Iron overload disorder  Pregnant or lactating women*  Use of contraception is required for females during the study. Male patients who are sexually active with a female of childbearing potential are allowed for study enrollment and will not require use of contraception