Clinical efficacy of serum PIVKA-II in the diagnosis and follow up after treatment of hepatocellular carcinoma

BACKGROUND/AIMS: Protein induced by vitamin K absence or antagonist II (PIVKA-II) appears to be a useful tumor marker for the evaluation of patients with hepatocellular carcinoma (HCC). But the usefulness of PIVKA-II was not yet clear in Korea where hepatitis B-virus is endemic. We investigated the usefulness of PIVKA-II in the diagnosis and follow-up after treatment of HCC. METHODS: We studied patients with HCC which was pathologically confirmed. PIVKA-II was measured by enzyme immunoassay. PIVKA- levels before and after treatment, in correlation with imaging studies, were analyzed for the comparison of treatment responses. Kappa index was obtained. RESULTS: A total of 129 patients were included. 93 patients (72%) were HBsAg positive. 86 patients (67%) were PIVKA-II >40 mAU/mL. 52 patients (40%) were AFP >20 ng/mL and 77 patients (60%) were AFP < or = 20 ng/mL. Of 77 patients, 40 patients (52%) showed PIVKA-II >40 mAU/mL. 68 of 129 patients were evaluated treatment response. On the basis of radiologic response, CR was 33, PR 17, SD 12, and PD 6. Of the 33 radiologic CR patients, 30 patients were CR and 3 patients were PR by means of PIVKA-II response. Of the 17 radiologic PR patients, 6 patients were CR and 7 patients were PR. Therefore, tumor responses by radiologic and PIVKA-II were well correlated (Kappa index was 0.59). CONCLUSIONS: PIVKA-II can be used as a useful tumor marker for patients with HCC, especially those with low levels of AFP, before and after treatment in Korea.