Carcinoma with shared pathologic characteristics of both hepatocellular carcinoma and cholangiocarcinoma

Performance evaluation of the Elecsys PIVKA‐II and Elecsys AFP assays for hepatocellular carcinoma diagnosis

Background and Aims

Prothrombin induced by vitamin K absence‐II (PIVKA‐II) is a serum biomarker linked to hepatocellular carcinoma (HCC), showing superiority to alpha‐fetoprotein (AFP) for early disease detection. We aimed to assess the clinical and analytical performance of the Elecsys® PIVKA‐II immunoassay in diagnosing HCC and evaluate PIVKA‐II's technical performance.

Methods

Serum samples from adult cases (i.e. patients with a first‐time HCC diagnosis; n = 168) and disease controls (i.e. patients without HCC with an at‐risk condition; n = 208) were assessed. An AFP cut‐off of 20 ng/mL was used to differentiate between HCC cases and disease controls. Clinical performance of the Elecsys PIVKA‐II assay was compared with that of comparator assays (Lumipulse G PIVKA‐II, μTASWako DCP, ARCHITECT PIVKA‐II) using receiver operating characteristic curve analysis to determine the area under the curve (AUC) values.

Results

The Elecsys PIVKA‐II assay compared favorably with comparator assays. Using a 28.4 ng/mL cut‐off, the Elecsys PIVKA‐II assay detected HCC with 86.9% sensitivity and 83.7% specificity. Clinical performance of the Elecsys PIVKA‐II assay (AUC: 90.8%) was equivalent to that of comparator assays (AUC: 88.3–89.6%). Relatively high PIVKA‐II concentrations were observed for cholangiocarcinoma and pancreatic cancer with the Elecsys assay in specificity panel analyses, indicating that high PIVKA‐II concentrations should not be used alone in the absence of other clinical data.

Conclusions

The Elecsys PIVKA‐II assay showed good analytical performance under routine laboratory conditions, comparing favorably with comparator assays. These findings support the suitability of the Elecsys PIVKA‐II assay as an aid in HCC diagnosis.

Vitamin K deficiency in critical ill patients; a prospective observational study

BACKGROUND

Vitamin K is a cofactor for proteins involved in cardiovascular health, bone metabolism and cancer. Measuring uncarboxylated prothrombin, also termed as "protein induced by vitamin K absence or antagonism for factor II (PIVKA-II)", has been used to assess vitamin K status. High levels may indicate vitamin K deficiency. The aim of this study was to measure PIVKA-II and prothrombin time (PT-INR) in intensive care (ICU) patients and correlate vitamin K status with mortality.

METHODS

Ninety-five patients admitted to the ICU had blood samples taken near admission and every third day. In addition to PIVKA-II and PT-INR, critical-care severity scores were computed.

RESULTS

The median baseline PIVKA-II was 4.97 μg/L compared to the upper reference of 2.0 μg/L. PIVKA-II further increased at days 3 and 6, (median 7.88 μg/L, p = .047 and median 8.14 μg/L, p = .011) predominantly in cardiac arrest patients (median 21.4 μg/L, day 3).

CONCLUSION

Intensive care patients have increased PIVKA-II levels at admission, which increases during the ICU stay, especially in cardiac arrest patients. There were no correlations between PIVKA-II and PT-INR, SOFA score or mortality. Further studies are needed to determine why PIVKA-II increases and whether high PIVKA-II levels in ICU patients affect long-term mortality or morbidity.