99Tcm-labelled anti-CEA monoclonal antibody for tumour immunoscintigraphy: first clinical results.
Twenty patients with malignant carcinoembryonic antigen (CEA)-producing tumour recurrences (colorectal n = 14; breast, lung, medullary thyroid carcinoma n = 2, each) were studied by immunoscintigraphy using an intact monoclonal anti-CEA antibody (BW 431/26) labelled with 99Tcm by a new labelling technique (Schwarz Method). This novel approach allows an almost quantitative labelling of the antibody, which is first reduced using a thiol, lyophilized in purified form, and then reacted with a stannous salt component before 99Tcm-pertechnetate binding. The labelling efficiency (as controlled by TLC) was greater than 95%, the in vitro stability at least 6 h. The imaging results (planar and SPECT) yielded a sensitivity of 91%, a specificity of 87% and a diagnostic accuracy of 90%. These first promising clinical results trigger the hope that the successful labelling of monoclonal antibodies with 99Tcm is a decisive step towards the more practically orientated use of tumour immunoscintigraphy.
Baum
R P
RP
Department of Radiology, J.W. Goethe University Hospital, Frankfurt/Main, FRG.
Hertel
A
A
Lorenz
M
M
Schwarz
A
A
Encke
A
A
Hör
G
G
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D002272:Carcinoembryonic Antigen / Q000276:immunology; D005260:Female; D006801:Humans; D007553:Isotope Labeling; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D013667:Technetium; D014055:Tomography, Emission-Computed
D000911:Antibodies, Monoclonal; D002272:Carcinoembryonic Antigen; D013667:Technetium