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).