An Imaging Agent (I-124 M5A) in Detecting CEA-Positive Liver Metastases in Patients With Colorectal Cancer

PRIMARY OBJECTIVES: I. To determine the ability of iodine I 124 monoclonal antibody M5A (124I-labeled M5A monoclonal antibody \[MAb\]) to localize to CEA positive gastrointestinal (GI) metastases primarily focused on the liver. SECONDARY OBJECTIVES: I. To determine the safety and pharmacokinetics of administration of 124I-labeled M5A MAb. II. To correlate the radiographic positron emission tomography (PET) images to the liver metastases pathology. III. To assess if the I-124 imaging agent detected additional liver and additional extra-hepatic liver lesions not appreciated on standard imaging scans. OUTLINE: Patients receive iodine I 124 monoclonal antibody M5A intravenously (IV) on day 0 and undergo PET scan on days 2 and 6. After completion of study, patients are followed up periodically for 1 year.