Detection of hepatocellular carcinoma with a new alpha-fetoprotein antibody imaging kit.
OBJECTIVE
The aim of this phase II study was to assess the clinical utility and safety of AFP-Scan (Immunomedics, Inc, Morris Plains, NJ), a technetium-99m (99mTc)-labeled anti-alpha-fetoprotein (AFP) Fab' imaging kit, in the evaluation of hepatocellular carcinoma (HCC), in comparison to computed tomography (CT).


METHODS
Twenty-five consecutive patients with a history of HCC were examined by planar and single-photon emission computed tomography (SPECT) imaging at 6 and 24 hours after intravenous (I.V.) injection of 1 mg AFP-Scan labeled with 925 MBq 99mTc.


RESULTS
In 20 patients, there was a specific binding of the Fab' antibody to the tumor, whereas in four patients who presented with elevated serum AFP levels, no specific targeting was found and no malignant lesions were evident by CT or biopsy. One patient was diagnosed as false-negative by AFP-Scan. In five of six patients with normal serum AFP levels, focal uptake was demonstrated. In one case, metastatic disease in the lower abdomen was found. In all patients, diagnostically relevant information was provided by the 24-hour antibody images, especially with SPECT. Comparing AFP-Scan versus CT, the former showed a higher sensitivity (95% v 63%) and specificity (67% v 17%), with an overall accuracy of 88% versus 52% for AFP-Scan versus CT, even in patients with normal serum AFP titers. No adverse reactions or human antimouse antibody (HAMA) elevations were found in any of the patients.


CONCLUSIONS
AFP-Scan appears to be a promising new antibody imaging kit for the disclosure of sites of HCC and should aid in the management of these patients by revealing primary, recurrent, and metastatic disease with a single imaging modality.
Dresel
S
S
Department of Nuclear Medicine, University of Munich, Klinikum Grosshadern, Germany.
Kirsch
C M
CM
Tatsch
K
K
Zachoval
R
R
Hahn
K
K
Goldenberg
D M
DM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000912:Antibodies, Neoplasm / Q000097:blood*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000276:immunology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D011933:Reagent Kits, Diagnostic; D013670:Sodium Pertechnetate Tc 99m; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D000509:alpha-Fetoproteins / Q000276:immunology* / Q000378:metabolism
D000912:Antibodies, Neoplasm; D019275:Radiopharmaceuticals; D011933:Reagent Kits, Diagnostic; D000509:alpha-Fetoproteins; D013670:Sodium Pertechnetate Tc 99m