Assessment of Stromal Invasion for Correct Histological Diagnosis of Early Hepatocellular Carcinoma
Figure 2
Histological features which make the assessment of stromal invasion difficult (a) True stromal invasion of very mild grade. The fibrous septum is almost intact except for a small area (arrow). (b) Pseudo-invasion consisting of very thin fibrous bundles within and around thick liver cell cords. This pattern was formed by dissection of liver parenchyma by very thin fibrous tissue. (c) A specimen of very poorly performed silver stain. (d) Silver stain of HCC tissue within and around a fibrous septum. Reticulin fibers circumscribing cancer tissue are seen even in the area of true invasion (yellow arrow). However, noncircumscribed tumor cells are also seen in the same fibrous septum (green arrows). This area is a “battle front” of invasion. Red arrows show ordinary tumor tissue with reticulin fibers surrounding the fibrous tissue.
