Noninvasive differentiation of benign from malignant disease has emerged as an important diagnostic challenge in the current age of health-care cost containment. Most physicians today acknowledge that early and accurate detection of cancer is important in successful treatment. Antibodies have been developed, labeled with radioactive isotopes, and used to detect and treat malignant tumors. During the past few years, several radiolabeled antibodies have received approval from the U.S. Food and Drug Administration for imaging colorectal, lung, ovarian, and prostate carcinomas, thus expanding and improving the physician's ability to detect and follow cancer in patients. At present, there is ample evidence in the literature to suggest that imaging with the 111In-labeled monoclonal antibody B72.3 is clinically useful for detecting primary/recurrent colorectal and recurrent ovarian carcinomas. In this article, we present a retrospective review of 136 patients from 10 moderate-sized hospitals who underwent a study with radioimmunoscintigraphy (RIS), using the 111In B72.3 antibody and standard diagnostic examinations for the detection of recurrent colorectal or ovarian carcinoma. The resulting data were analyzed in an effort to determine if (and how) information obtained from this radioimmunoscintigraphic procedure is being used by referring physicians. Our findings suggest a gradually increasing use of scan findings with the 111In B72.3 antibody in making patient-management decisions.