Idiopathic benign biliary strictures in surgically resected patients with presumed cholangiocarcinoma

Abstract

Objective: Distinguishing between malignant and benign biliary strictures remains problematic. The aim of this study was to compare and contrast the clinical features of patients with benign and malignant biliary strictures.

Methods: Medical records of patients who underwent surgical resection for presumed cholangiocarcinoma were reviewed. Immunohistochemistry for hypoxia inducible factor-1-alpha (HIF-1-alpha) was performed on all bile ductule samples.

Results: Twelve patients with benign strictures (group I) were compared to 26 patients with cholangiocarcinoma (group II). Group I was predominantly female (ratio 2: 1), (p<0.01), whereas the gender ratio was 1: 1 in patients in group II. Bismuth-Corlette type strictures in group I were more likely to be type I/II, whereas type III strictures predominated in group II. The CA 19-9 was <100 U/ml in 6 and >100 U/ml in 1 patient of group I and <100 in 13 and >100 in 11 patients in group II. Half of the patients in group I had positive immunoreactivity for HIF-1-alpha in bile ductules.

Conclusion: Benign biliary strictures masquerading as cholangiocarcinomas occur more often in women, are less often Bismuth-Corlette type III, have serum CA 19-9 values <100 U/ml, and hypoxia may play a role in a subset of these strictures.

Figure 1.

Cholangiogram of a benign inflammatory bile duct stricture masquerading as cholangiocarcinoma. This representative cholangiogram epitomizes the difficulty in distinguishing between malignant and benign biliary strictures via ERC. There is lack of visualization of the right hepatic ductular system with left ductular dilatation.

Figure 2.

Hypoxia inducible factor-1-alpha (HIF-1-alpha) is present in benign inflammatory bile duct strictures. Representative photomicrographs of biliary duct tissue specimens after immunohistochemical staining of HIF-1-alpha. (A) Positive staining of HIF-1-alpha in ductular epithelium (magnification ×20). (B) A higher magnification of (A) illustrating definite nuclear staining (arrows) (×40). (C) A biliary tissue specimen negative for HIF-1-alpha; note the lack of nuclear staining in ductular epithelium and clear nuclei.