Clinical application of radioimmunolocalization in colorectal cancer

We present preliminary results of radioimmunolocalization (RIL) of colorectal cancer with 131I labelled F(ab')2 fragments from monoclonal anti CEA and anti CA 19.9 antibodies in 22 patients with colorectal cancer and in one patient with metastases of unknown origin and high CEA value. Positive images were obtained in 7 of 11 primary tumors from 10 patients evaluated preoperatively; in 2 of 3 recurrences; in 9 of 12 metastatic localizations and in the unknown primary tumor localized, finally in the cecum. One local recurrence was not detected by any diagnostic methods, but RIL. There was not false-positive images. Therefore, RIL appears as a promising method for the diagnosis and follow-up of colorectal cancer.