Pathology underrates colon cancer extranodal and nodal metastases; ex vivo radioimmunodetection helps staging.

Purpose: Colorectal carcinoma is frequently accompanied by small lymph nodes metastases that often escape pathologic examination. We evaluated whether ex vivo radioimmunodetection with the Affinity Enhancement System (AES) could improve detection of mesocolonic metastases.

Experimental Design: A bivalent 111In-labeled hapten was injected (16 patients) 4 days after a bispecific antibody (anticarcinoembryonic antigen, antihapten).