Mediastinal Yolk Sac Tumor Producing Protein Induced by Vitamin K Absence or Antagonist-II

Protein induced by vitamin K absence or antagonist II: Experience to date and future directions

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer with high mortality. The realization of precision medicine in HCC relies upon efficient biomarkers. Protein induced by vitamin K absence or antagonist II (PIVKA-II) is an immature prothrombin with insufficient coagulation activity, overexpressing in HCC cells. Previous evidence confirmed the role of PIVKA-II in screening and diagnosing HCC. However, the increased PIVKA-II was observed not only in HCC, but also in non-HCC individuals such as vitamin K deficiency. The joint detection of PIVKA-II and other biomarkers could significantly improve diagnostic accuracy in HCC. Furthermore, PIVKA-II serves as a valuable prognostic predictor, transplantation eligibility, resectability, tumor recurrence, therapeutic efficacy, and malignant tumor behaviors. Additionally, PIVKA-II represents a potential target for agent development to establish new therapeutic strategies. Besides HCC, PIVKA-II also serves as a biomarker of vitamin K status. In this review, we assess the role of PIVKA-II in diagnosis, prediction, and treatment. Over the past decades, substantial progress has been achieved in the application of PIVKA-II. Exploration and innovation are required for further advances in the field of PIVKA-II investigation.

Pineal Yolk Sac Tumor Producing α-Fetoprotein Detected by 68Ga-FAPI PET/MRI

ABSTRACT

Pineal yolk sac tumors (YSTs) are a rare type of extragonadal YST. They make up a small fraction of all intracranial germ cell tumors and an even small fraction of pineal masses overall. This study reported a case of pineal YST with α-fetoprotein production revealed by 18F-FDG and 68Ga-FAPI PET/MRI. In the PET images, 68Ga-FAPI showed a far better tumor-to-background ratio than 18F-FDG in the pineal YST because there is little 68Ga-FAPI uptake in the brain. This case indicates that 68Ga-FAPI PET/MRI may be a useful tool for evaluating intracranial YST and other types of tumors in central nervous system.

Protein induced by vitamin K absence or antagonist II (PIVKA-II) producing large cell neuroendocrine carcinoma (LCNEC) of lung with multiple liver metastases: A case report

A 78-year-old man was admitted to our hospital for multiple lung and liver tumors. Initial clinical diagnosis was hepatocellular carcinoma (HCC) with lung metastases because of a high value of serum protein induced by vitamin K absence or antagonist II (PIVKA-II) (6,705 mAU/mL). However, a review of a prior CT showed the lung tumor had existed 6 months before liver tumors were detected. The tumors progressed rapidly and the patient died 37 days after admission. Autopsy revealed that both lung and liver tumors exhibited the histology of large cell neuroendocrine carcinoma (LCNEC). Immunohistochemistry revealed that the tumor cells expressed not only neuroendocrine markers but also PIVKA-II diffusely. Hepatoid differentiation was not detected. Background liver did not show any chronic liver disease. The final diagnosis was PIVKA-II producing LCNEC of the lung with multiple liver metastases. PIVKA-II producing tumors other than HCC are extremely rare. To our best knowledge, this is the first case report of PIVKA-II producing neuroendocrine tumors of the lung.