BREAST-CARCINOMA DETECTION WITH A COMBINATION OF RADIOLABELED MONOCLONAL-ANTIBODIES - PROMISING RESULTS FROM IMMUNOHISTOCHEMISTRY STUDIES

BACKGROUND. Recent studies have demonstrated that the use of radiolabe Ied monoclonal antibodies (MoAbs) directed against tumor-associated an tigens could help in the recognition of primary tumors, their extent, and their metastases by external scintigraphy (used preoperatively) or by hand-held gamma-detecting probe (GDP) (used intraoperatively). MET HODS. The authors evaluated carcinoembryonic antigen (CEA), c-erb B-2 protein, and TAG-72 expression in 100 cases of breast carcinoma using F023C5 (anti-CEA), B72.3, and anti-c-erb B-2 protein MoAbs that were p reviously investigated for their usefulness in radioimmunoguided surge ry and external scintigraphy. The goal of this study was to examine th e biodistribution of each antibody in primary, multifocal, and metasta tic lesions to evaluate the suitability of their simultaneous use in G DP and external scintigraphy, RESULTS. Results showed immunoreactivity for c-erb B-2 protein in 39 of 99 cases, for B72.3 in 41 of 100 cases , and for CEA in 15 of 100 cases. Multifocal lesions demonstrated posi tivity for c-erb B-2 protein in 37.4% of cases (6 of 16), for B72.3 in 68.8% of cases (11 of 16), and for CEA in 6.2% of cases (1 of 16). In lymph node metastases, immunoreactivity was found for c-erb B-2 prote in in 36.4% of cases (12 of 33), for B72.3 in 63.7% of cases (21 of 33 ), and for CEA in 24.3% of cases (8 of 33). When the authors considere d the immunoreactivity of all three MoAbs, the percentage of positive cases they observed was 60% in primary tumors (60 cases), 78% in lymph node metastases, and 81.2% in multifocal lesions, CONCLUSIONS. These results suggest that in vivo tumor radioimmunodetection could be impro ved by tile use of more antibodies directed against different tumor as sociated antigens. (C) 1996 American Cancer Society.