[Immunoscintigraphy with MAb B72.3 for preoperative detection of lymph node metastases of colorectal carcinoma].

From April 1, 1992 to December 31, 1993 we investigated 30 patients with suspected primary colorectal carcinoma or questionable tumor relapse by immunoscintigraphy prospective with the monoclonal antibody MAb B72.3 in order to detect the tumor and especially regional lymph node metastases. All the patients underwent surgical treatment. The diagnosis was based on surgery and biopsy. The diagnostic sensitivity of immunoscintigraphy in detecting the tumor was 76%, the specificity 94% (predictive value positive [PVP] 95%) and 43%, respectively 85% in detecting lymph node metastases (PVP 60%). The diagnostic sensitivity in detecting rectosigmoid tumors was 79 and 60% in detecting lymph node metastases of rectosigmoid carcinoma (PVP 60%). The specificity was 90%. It could be shown, that the detection of metastases in singularly lymph nodes smaller than 1 cm was not possible and often a final decision could not be done. We conclude, that the benefit of this method in detection of lymph node metastases compared to basic diagnostic, expenses and costs is doubtfully.