The value of immunoscintigraphy in the detection of recurrent colorectal cancer

The aim of this prospective study was to determine whether anti-carcinoembr yonic antigen (anti-CEA) scintigraphy is a useful additional technique in t he diagnosis recurrence of colorectal cancer. Forty patients with suspected recurrence of colorectal cancer, underwent immunoscintigraphy (IS) and hel ical computed tomography (CT) in the 2 weeks before surgery. Surgical findi ngs were used to evaluate the performance of the imaging techniques. Suspec ted areas on IS and CT were systematically explored. Helical CT was found t o be superior to IS for the liver, the sensitivity and specificity of CT be ing 100% and 90%, respectively, vs 53% and 100% for IS. However, IS was bet ter than CT for the detection of extra-hepatic abdominal recurrence: sensit ivity and specificity of IS were 100 and 82%. respectively vs 33 and 82% fo r CT. Seven cases of peritoneal carcinomatosis were overlooked by helical C T. Our results indicate that IS improves detection of extra-hepatic abdomin al recurrence of colorectal cancer. Immunoscintigraphy is valuable as a gui de to the treatment strategy and operative procedures. ((C) 2001 Lippincott Williams & Wilkins).