Published online Aug 21, 2014. doi: 10.3748/wjg.v20.i31.10908
Revised: May 9, 2014
Accepted: July 11, 2014
Published online: August 21, 2014
Processing time: 181 Days and 22.7 Hours
AIM: To investigate if loss of epithelial cell adhesion molecule (EpCAM) is associated with microinvasion in hepatocellular carcinomas (HCCs) in the presence of chronic hepatitis B.
METHODS: The expression of EpCAM, cytokeratin 7 (CK7) and CK19 in 112 hepatic nodules was studied, including 20 HCCs with nodules ≤ 3 cm, 26 HCCs with nodules > 3 cm, 20 high-grade dysplastic nodules, 26 cirrhotic, large regenerative nodules and 20 cases of cirrhosis.
RESULTS: Membranes of ductular reaction (DR) hepatobiliary cells, interlobular bile duct and some hepatic cells were positive for EpCAM expression. Active expression of DR/EpCAM was observed in the majority of noninvasive nodules (50/66, 75.76%); however, expression was absent in the major area of invasion in HCCs (42/46, 91.30%). DR/EpCAM loss in HCCs ≤ 3 cm was higher than in high-grade dysplastic nodules (HGDNs) (P < 0.05), cirrhotic, large regenerative nodules and cirrhosis (P < 0.01). Furthermore, patients (20 HCCs ≤ 3 cm, 26 HCCs > 3 cm, 20 HGDNs) with DR/EpCAM expression had a higher overall survival rate (P < 0.01) and lower early recurrence rate (P < 0.01). DR/EpCAM expression showed a close relationship with DR/CK7 and DR/CK19 expression (P < 0.01). The area under the receiver operating characteristic (ROC) curve of DR/EpCAM was similar to that of DR/CK7 and DR/CK19 (P > 0.05). The diagnostic specificity and diagnostic accuracy were both increased when DR/EpCAM, DR/CK7 and DR/CK19 were combined (P < 0.01).
CONCLUSION: DR/EpCAM loss may be a useful marker for determining microinvasion in HCCs ≤ 3 cm, but also for predicting prognosis.
Core tip: Epithelial cell adhesion molecule (EpCAM) may be a new marker of ductular reaction (DR) in routine pathology. We observed the morphological features of DR/EpCAM in 112 small hepatic nodules and compared this with DR/cytokeratin 7 (CK7) and DR/cytokeratin 19 (CK19). The diagnostic value of DR/EpCAM was similar to DR/CK7 and DR/CK19; however, the diagnostic accuracy and specificity increased when these parameters were combined. Therefore, DR/EpCAM loss was confirmed to be a useful marker not only for determining microinvasion in HCCs ≤ 3 cm, but also for predicting prognosis.