Cytopathology: SS06-1 A WELL-DIFFERENTIATED HEPATOCELLULAR NODULAR LESION IN THE LIVER OF A WOMAN.

The differential diagnoses of fine needle aspiration (FNA) biopsy of a well-differentiated hepatocellular nodule (WDHN) in a woman with hepatitis B cirrhosis are discussed. Radiological diagnosis was a large regenerative nodule containing fat.Establish representative sampling.In cirrhosis, differential diagnosis include large regenerative nodule, dysplastic nodule (low- or high-grade), and early to progressed hepatocellular carcinoma (HCC). A nodule-in-nodule lesion occurs when there is malignant transformation in a benign parent nodule. Focal nodular hyperplasia and hepatocellular adenoma are less likely.Fatty change is common in WDHNs; diagnostic pitfalls include steatosis and focal fatty change.In WDHNs, the diagnostic dilemma is proof of malignancy.Serum α-fetoprotein has low sensitivity.Key cytological features in highly well-differentiated HCC: Generally cellular aspirates; monomorphous hepatocyte population with tendency to dispersion; small monotonous tumor cells with increased nuclear-cytoplasmic ratio, nuclear crowding, and scant thick cytoplasm; transgressing but no peripheral endothelium; and lack of bile duct cells.Polymorphous hepatobiliary population +/- restoration features (such ductules) favor benign nonneoplastic WDHN, after excluding non-representative sampling.Novel immunohistochemical markers such as glypican-3, glutamine synthetase and heat shock protein 70 may be helpful as an indicator of hepatocellular malignancy if any two markers are positive.Recommend combined cytohistological approach.