• The present study was undertaken to determine whether an anti—carcinoembryonic antigen (CEA) monoclonal antibody (MAB), labeled with the potent beta emitter yttrium 90, could alter the growth of diffuse intraperitoneal carcinomatosis of colon cancer. Nude mice bearing the CEA-producing human tumor line LS174T received therapy with the anti-CEA MAB ZCE025 90Y. Animals were evaluated 12 days after therapy. Untreated animals had a mean (±SEM) tumor burden of 3.99±0.10 g, while animals treated with ZCE025 90Y had 0.29±0.04 g present. This decrease was significant compared with the 1.31 ±0.16 g of tumor present in animals treated with a 90Y-labeled nonspecific antibody 96.5c. The therapeutic effects seen with ZCE025 90Y suggest a potentially useful role for 90Y-labeled anti-CEA MABs in the treatment of gastrointestinal carcinomatosis.
(Arch Surg 1987;122:1333-1337)