Aberrant cytokeratin 7 expression of centrilobular hepatocytes: a clinicopathological study

Aims: This study has attempted to elucidate the clinicopathological features of aberrant cytokeratin 7 (CK7) expression by centrilobular hepatocytes. Methods and results: A total of 113 liver biopsy specimens from patients with common non-neoplastic liver diseases, including hepatitis B or C, non-alcoholic steatohepatitis, alcoholic liver disease and other diseases were examined. In 56 specimens (49.6%), CK7-positive centrilobular hepatocytes (CK7 + CHs) were identified and sometimes showed binuclear features. CK7 + CHs were associated with patients older age (P = 0.004), higher serum levels of aspartate aminotransferase (P = 0.016) and gamma-glutamyltransferase (P = 0.006), centrilobular fibrosis (P < 0.001), prominent thickening of hepatocytic plates (P < 0.001) and higher scores of total and periportal CK7-positive hepatocytes (both P < 0.001), but were not correlated with gender, steatosis, serum levels of total bilirubin or alanine aminotransferase. In 55 cases of hepatitis B and hepatitis C only, CK7 + CHs were related to a higher stage of fibrosis (P = 0.006). Conclusion: CK7 + CHs occur relatively frequently in non-neoplastic liver disease, associated with centrilobular scarring and the presence of CK7-positive periportal hepatocytes, and appear to be a non-specific phenomenon with respect aetiology of underlying disease. CK7 + CHs may represent age-dependent activation of hepatic progenitor cells or a regenerative phenomenon of hepatocytes themselves, both of which might contribute to liver regeneration.