Cytologic Comparison Between Malignant and Regenerative Nodules in the Background of Cirrhosis

BACKGROUND: Incidence of hepatocellular carcinoma has been increased as the sixth most common cancer in the world. Improvement in imaging techniques has decreased the need for tissue confirmation in diagnosis of hepatocellular carcinoma (HCC). Meanwhile, false negative and positive cases are present. Fine needle aspiration (FNA) biopsy can be helpful to identify well-differentiated HCCs with low risk of vascular invasion and better prognosis following transplantation. OBJECTIVES: We conducted this study to find useful criteria for cytological differential diagnosis between nodules of well differentiated hepatocellular in the background of cirrhosis and pure cirrhotic regenerative nodules in cytology smears. MATERIALS AND METHODS: 140 fine needle aspirations (FNA) of fresh cirrhotic hepatectomy specimens were studied (100 pure regenerative nodules and 40 HCC nodules). All slides were reviewed by two expert pathologists. The most useful criteria were selected and evaluated in 560 cytology smears stained by Pap and Wright methods. RESULTS: None of the smears from cirrhotic patients showed mitosis, transgressing endothelium, eccentric nuclei, and scant cytoplasm, but thick nuclear membrane, spindle cells and abundant, thick and monotonous cytoplasm were found in many cases with cirrhosis. Large nucleoli (2 %), multiple nucleoli (6 %), increased N/C ratio (4 %), and broad cores (2 %) were found very rarely in the smears of regenerative nodules, but they were present in 50 %, 72.5 %, 87 %, and 77.5 % of HCC nodules, respectively. CONCLUSIONS: Combination of cytologic criteria can be helpful for differential diagnosis between HCC and regenerative nodules.