Fig. 4

The arrow in (a) showed patent microscopic invasion of a vessel by neoplastic cells (H&E staining; magnification X100). With anti-CD34 immunohistochemistry (b), vascular invasion was confirmed by the presence of small nests of malignant cells inside the vessels (magnification X200). Log values of serum levels of AFP (c) and PIVKA-II (d) in HBV-related HCC with and without vascular invasion were compared by box plots. AFP: alpha fetoprotein, PIVKA-II: protein induced by vitamin K absence-II. *P < 0.05 and **P < 0.01