Hepatocellular carcinoma (HCC) remains the leading cause of cancer-related mortality worldwide, particularly in areas with high hepatitis B virus prevalence. Early detection is challenging due to the limited sensitivity of conventional biomarkers such as alpha-fetoprotein (AFP). Protein induced by the absence of vitamin K or antagonist-II (PIVKA-II), an aberrant prothrombin variant, has emerged as a promising serological biomarker with significant diagnostic, prognostic, and therapeutic relevance in HCC. This review synthesizes current knowledge on the molecular basis, clinical utility, and future directions of PIVKA-II in HCC management.
Import
HCC is the most common form of primary liver cancer, often diagnosed at an advanced stage due to its asymptomatic onset. AFP deficiency, especially in AFP-negative HCC (AFP-NHCC), highlights the need for more reliable biomarkers. PIVKA-II, first identified in 1984, has gained attention for its close relationship with tumor biology and its superior diagnostic yield in some clinical contexts.
Biological significance and characteristics of PIVKA-II
PIVKA-II, also known as des-γ-carboxyprothrombin (DCP), is produced under conditions of vitamin K deficiency or competition. In HCC, its production is associated with hypoxia, reduced vitamin K levels, and reduced γ-glutamyl carboxylase activity. Structurally, PIVKA-II lacks normal coagulation function due to incomplete carboxylation of glutamic acid residues in its Gla domain. Besides being a metabolic byproduct, PIVKA-II actively promotes HCC progression by activating oncogenic pathways such as c-Met/JAK1/STAT3 and Ras/Raf/MEK/ERK and stimulating angiogenesis through the KDR/PLCγ/MAPK axis. A specialized variant, next-generation DCP (NX-DCP), shows higher specificity for HCC and correlates with microvascular infiltration and tumor burden.
PIVKA-II as a HCC biomarker
Early detection:
PIVKA-II demonstrates higher diagnostic sensitivity and specificity than AFP, particularly in AFP-NHCC and in tumors ≥5 cm. Guidelines from the Japanese Society of Hepatology and the Chinese Guidelines for the Diagnosis and Treatment of Primary Liver Cancer support its use in high-risk populations. To improve early detection, multiparametric models such as GALAD, GAAD, ASAP, and aMAP integrate PIVKA-II with demographic and biochemical variables, greatly enhancing diagnostic accuracy and enabling dynamic risk stratification.
Differentiation of HCC from intrahepatic cholangiocarcinoma (ICC):
While PIVKA-II shows limited elevation in ICC, its combination with other markers (eg, CA19-9, CA125) in nomograms improves the differential diagnosis. The interaction between PIVKA-II and hepatitis B virus status further helps distinguish HCC from ICC.
Efficacy assessment and prognostic analysis:
PIVKA-II serves as a valuable tool for predicting treatment response and prognosis in various HCC treatments—including resection, ablation, transarterial chemoembolization, immunotherapy, and targeted therapy. Elevated baseline levels and dynamic changes in PIVKA-II correlate with tumor invasiveness, risk of relapse, survival outcomes, and even adverse events during immunotherapy. Reductions in PIVKA-II after treatment are associated with better clinical outcomes and longer recurrence-free survival.
Comparative analysis with other biomarkers
Compared to AFP, AFP-L3, glypican-3 (GPC3), and neutrophil-to-lymphocyte ratio (NLR), PIVKA-II has advantages in early detection, applicability to various etiologies, and monitoring of therapeutic response. However, its performance varies by tumor size, etiology, and geographic population, necessitating combined use with other markers for optimal clinical utility.
Shortcomings and future prospects
Detection methods:
Current immunoassays (ELISA, CLEIA) are confounded by vitamin K deficiency, anticoagulant therapy, and liver disease. Standardization of assays and cutoff values across platforms and populations is urgently needed. Emerging sensor technologies and next-generation assays promise to improve specificity and clinical applicability.
PIVKA-II in non-HCC diseases:
Elevated PIVKA-II is also seen in non-HCC conditions, such as gallbladder cancer, pancreatic cancer, chronic kidney disease, and vitamin K deficiency states. This broadens its potential clinical relevance, but also requires careful interpretation within a comprehensive diagnostic context.
Future directions:
Integrating PIVKA-II with artificial intelligence and deep learning can enhance early diagnosis and prognostic stratification. Further research is needed to clarify its role as a guide versus surrogate for malignancy, to standardize detection protocols, and to validate its utility in a variety of clinical and etiological settings.
Conclusion
PIVKA-II has evolved from a serological abnormality to a cornerstone biomarker in the diagnosis, prognosis and treatment monitoring of HCC. Its incorporation into multiparametric models and clinical guidelines underscores its translational value. Future efforts should focus on assay standardization, mechanistic insights, and individualized implementation to fully exploit its potential in improving HCC outcomes.
