BACKGROUND
The relationship between hepatoliths and cholangiocarcinoma is etiologically unclear. However, histogenetic sequencing with hyperplasia, dysplasia and carcinoma can occur in the bile ducts of hepatolithiasis.
METHODS
We studied 55 cases of hepatolithiasis and examined the specimens of resected liver tissue with a microscope.
The growth patterns of bile duct epithelium were divided into four types: flat, tufting, micropapillary and papillary. The dysplasia was also divided into low-grade dysplasia (LGD) and high-grade dysplasia (HGD).
RESULTS
Of 55 cases of hepatolithiasis, 30 cases (54.6%) were of the flat pattern, 13 cases (23.6%) the micropapillary pattern, and 11 cases (20%) the tufting pattern. Epithelial hyperplasia was noted in only 36 cases (65.5%) in the large bile ducts, but dysplastic changes were found in 19 cases. Of 19 cases of dysplasia, LGD was present in 14 cases (25.5% of total 55 cases) an HGD in 5 cases (9% of total 55 cases). The epithelial hyperplasia showed histologic growth of the flat pattern in 29 cases out of 36 cases. But LGD (14 cases) had 6 cases of the tufting pattern and 7 cases of the micropapillary pattern. HGD (5 cases) revealed 4 cases of the micropapillary pattern with one case of the tufting pattern.
CONCLUSION
This study suggests that sequences of hyperplasia, low-grade dysplasia and high-grade dysplasia can play a role in the carcinogenesis of bile duct epithelium in hepatolithiasis with the histologic pattern changing from flat to micropapillary growth.