Clinical application of a new monoclonal antibody (19B7) against PIVKA-II in the diagnosis of hepatocellular carcinoma and pancreatobiliary malignancies.
OBJECTIVE
A new monoclonal antibody (19B7) against prothrombin induced by vitamin K absence or antagonist-II (PIVKA-II) was clinically applied in patients diagnosed with hepatocellular carcinoma and pancreatobiliary malignancies, and the results were compared with those obtained using the conventional monoclonal antibody (MU-3) against PIVKA-II.


METHODS
The assays were the standard E-1023 using MU-3, a high sensitivity kit using MU-3 and a highly sensitive avidin-biotin complex method, and a new monoclonal antibody (19B7) kit.


RESULTS
The rate of PIVKA-II positivity in patients with hepatocellular carcinoma (n = 182) was 44% with E-1023, 55.5% with the high sensitivity kit, and 58.2% with the new monoclonal antibody kit. Small liver cancers <2 cm in diameter (n = 45) had a positivity rate of 15.6% with E-1023, 26.7% with the high sensitivity kit, and 31.1% with the new monoclonal antibody kit. The incidence of PIVKA-II positivity in patients with pancreatobiliary carcinoma (n = 91) was 29.7% with the high sensitivity kit and 52.7% with the new monoclonal antibody kit. The PIVKA-II ratio (plasma concentration with the high sensitivity kit/plasma concentration with the new monoclonal antibody kit) was calculated as > 1.0 in 89 of the 113 (78.8%) patients with hepatocellular carcinoma with the new monoclonal antibody kit assay level above 0.002 arbitrary units/ml, compared with <1.0 in almost all patients with pancreatobiliary malignancies.


CONCLUSIONS
MU-3 has much greater affinity for PIVKA-II in hepatocellular carcinoma than does 19B7, whereas 19B7 has much greater affinity for PIVKA-II in pancreatobiliary malignancies than does MU-3. The new monoclonal antibody, 19B7, is useful for diagnosing hepatocellular carcinoma and can also distinguish patients with hepatocellular carcinoma from those with other pancreatobiliary malignancies when combined with a PIVKA-II assay using the conventional monoclonal antibody, MU-3.
Nakao
A
A
Department of Surgery II, Nagoya University School of Medicine, Showa-ku, Japan.
Taniguchi
K
K
Inoue
S
S
Takeda
S
S
Harada
A
A
Nonami
T
T
Watanabe
K
K
Takagi
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014670:Ampulla of Vater / Q000473:pathology; D000911:Antibodies, Monoclonal / Q000145:classification; D001650:Bile Duct Neoplasms / Q000097:blood / Q000175:diagnosis; D001661:Biliary Tract Neoplasms / Q000097:blood / Q000175:diagnosis*; D015415:Biomarkers; D014408:Biomarkers, Tumor / Q000097:blood; D002277:Carcinoma / Q000097:blood / Q000175:diagnosis; D006528:Carcinoma, Hepatocellular / Q000097:blood / Q000175:diagnosis*; D003138:Common Bile Duct Neoplasms / Q000097:blood / Q000175:diagnosis; D005260:Female; D005706:Gallbladder Neoplasms / Q000097:blood / Q000175:diagnosis; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D008113:Liver Neoplasms / Q000097:blood / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D011498:Protein Precursors / Q000032:analysis*; D011516:Prothrombin / Q000032:analysis*; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; D015415:Biomarkers; D014408:Biomarkers, Tumor; D011498:Protein Precursors; C008208:acarboxyprothrombin; D011516:Prothrombin