Bile duct strictures are problematic in terms of management and distinction between benign and malignant.
There are numerous causes of biliary duct strictures, including 1,2:
Although identification of malignant cells on washings obtained during ERCP can make the diagnosis, they are negative in 25-50% of cases 1. Careful imaging is therefore often required.
The distinction between malignant and benign structures relies on two aspects:
- morphology of the stricture
- associated findings, pointing to a cause
As far as assessing the morphology of the stricture, modalities that image the lumen (ERCP, MRCP, CT intravenous cholangiograms) are best, whereas to assess for associated features US or CT/MRI are better.
Benign features include 2:
- tapered margins
Malignant features include:
- shouldered margins
- thickened (>1.5 mm) and enhancing (on arterial and or portal venous phase) duct walls 2
It is often difficult to distinguish between malignant and benign strictures, especially if short 2.
Associated findings are for example:
- features of chronic pancreatitis
- evidence of previous cholecystectomy
- lymph node enlargement
- infiltrating mass
Treatment and prognosis
Treatment and prognosis clearly depend on the underlying etiology.
For benign stricture and number of options exist, including:
- cholangioplasty: percutaneous or retrograde balloon dilation 3
- stent placement: only considered in failed cholangioplasty and no other surgical options
- surgery with resection of the stenotic segment and re-anastomosis or choledochoenterostomy (e.g. Roux-en-Y)
- 1. Babu S, Smithson J. Bile duct stricture: benign or malignant? J R Soc Med. 2002;95 (6): 302-4. J R Soc Med (link) - Free text at pubmed - Pubmed citation
- 2. Choi SH, Han JK, Lee JM et-al. Differentiating malignant from benign common bile duct stricture with multiphasic helical CT. Radiology. 2005;236 (1): 178-83. doi:10.1148/radiol.2361040792 - Pubmed citation
- 3. Bonnel DH, Liguory CL, Lefebvre JF et-al. Placement of metallic stents for treatment of postoperative biliary strictures: long-term outcome in 25 patients. AJR Am J Roentgenol. 1997;169 (6): 1517-22. AJR Am J Roentgenol (abstract) - Pubmed citation
- 4. Venkata S. Katabathina, Anil K. et al. Adult Bile Duct Strictures: Role of MR Imaging and MR Cholangiopancreatography in Characterization. (2014) RadioGraphics. 34 (3): 565-86. doi:10.1148/rg.343125211 - Pubmed