[Further study on the value of M2-type pyruvate kinase in the diagnosis of primary hepatocarcinoma].

Based on the pilot study of plasma M2-type pyruvate kinase (M2-PyK) in the diagnosis of primary hepatocarcinoma, some improvements in methodology were made. M2-PyK was purified directly from human placenta, and anti-human M2-PyK antibody was raised in rabbits. The purified antibody IgG was degraded into Fab' fragment and cross-linked with horseradish peroxidase (HRP) to prepare Fab'-HRP conjugate. By using sandwich Fab'-ELISA, M2-PyK in the plasma was determined in 119 healthy adults, all gave values less than 2.35 ng/ml, with 80 percent less than 1.2 ng/ml, and the medium was 0.68ng/ml. There was no significant difference between male and female subjects. The plasma M2-PyK in 32 cases of primary hepatocarcinoma was markedly increased with a range of 1.31-30.13ng/ml or 7.06 +/- 5.25 ng/ml, which was more than 10 fold of the normal medium value. If 2.35 ng/ml was taken as the upper limit of the normal range, the positive rate was up to 90.6%. Seven cases of hepatocarcinoma with AFP less than 50 ng/ml, M2-PyK was positive. The result was the same as that in our previous report. Other primary malignant tumors of the liver origin were also positive, whereas the benign tumors of the liver were negative. In 53 cases of the carcinomas in gastro-intestinal tract, whether the carcinomas were metastasized to the liver or not, a positive rate of 40.6-52.3% was shown which was higher than that in the cases of colorectal carcinoma. Hence, this method was not specific for the diagnosis of primary hepatocarcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)