Head and neck cancer localization with indium labelled carcinoembryonic antigen: a pilot project

Antibodies reacting with cancer cells are playing an increasing role in cancer detection. Most antibodies under study are directed at onco-fetal proteins, principally carcino-embryonic antigen (CEA). In terms of imaging, most work has concentrated on the abdominal and pelvic regions. Although the majority of primary head and neck cancers are amiable to clinical identification, detection of regional metastases and recurrences following radiotherapy can be difficult. Antibody to CEA was radiolabelled with Indium-111 and used to identify proven head and neck tumors by external imaging. In seven patients with squamous cell tumors, five of five primary sites and two of three secondary sites were imaged satisfactory. Comparison with conventional scanning showed good correlation. There were no false positive scans, no consistent relationship between serum or tissue CEA levels and the success of imaging was evident. The success of this pilot study should encourage the search for more tumor-specific antigens, and further studies of external scintigraphic techniques in the localization of head and neck cancers.