Immunocytochemical staining of Kupffer and endothelial cells in fine needle aspiration cytology of hepatocellular carcinoma

OBJECTIVE: To evaluate the significance of the presence of Kupffer and endothelial cells in distinguishing hepatocellular carcinoma (HCC) and adenocarcinoma (AC) on cytologic smears. STUDY DESIGN: Fine needle aspiration biopsies (FNABs) from 43 cases, 21 HCC and 22 AC (8 primary and 14 metastatic), were immunostained for Factor VIII and vimentin as markers for endothelial cells and Kupffer cells, respectively. Cytologic diagnosis was verified by histologic and/or clinical follow-up. RESULTS: Eighteen of the 21 cases (86%) of HCC and 11 (5 primary and 6 metastatic) of 22 cases (50%) of AC showed positive immunostaining for Factor Vm (P = .02). Vimentin immunostaining was positive in 55% of HCCs and 41% of ACs (P = .74). Forty-five per cent of cases of AC showed immunostaining for both Factor VIII and vimentin, while 22% of cases of AC showed immunostaining for both Factor VIII and vimentin (P = .18). CONCLUSION: Immunocytochemical identification of endothelial cells using Factor VIII may have important diagnostic value in separating HCC from adenocarcinomas in liver FNABs. The presence gf Kupffer cells labeled with vimentin has no diagnostic significance in FNAB of these tumors.