Scintigraphic detection of colon carcinomas with iodinated monoclonal antibodies

The aim of this study was to evaluate the clinical reliability of the immunoscintigraphy with iodinated monoclonal antibodies for the detection of metastases and recurrences of colon carcinomas.

A total of 45 patients with colon carcinoma was investigated with gamma camera, after intravenous application of iodinated monoclonal antibodies.

The sensitivity of the method was 90%, specificity 86%, positive predictive value 93%, negative predictive value 80% and accuracy 87%. There was statistically significant relationship between immunoscintigraphic and ultrasonographic (US) findings (p=0.005). Also, there was significant relationship between immunoscintigraphy and Dukes stage (p=0.019). Tumor marker levels were not significantly correlated with immunoscintigraphic findings (p<0.05). Significant difference was noted in patients with positive findings for malignancy on US and immunoscintigraphic findings (p=0.006), i.e. patients with positive findings for malignancy had more frequently immunoscintigraphic findings of malignancy. Correlation with other diagnostic procedures (rectoscopy, colonoscopy, CT) did not show significant correlations.

We conclude that immunoscintigraphy can be helpful in the detection of metastases and recurrences of colon carcinomas.