Biliary intraepithelial neoplasia
Before 2005, biliary atypia or biliary dysplasia were terms usually employed to refer to BilIN 5.
The incidence of BIlIN is unknown, with these lesions usually identified in the resected specimens of cholangiocarcinoma or, less commonly, elective cholecystectomies.
It has been implicated to be more frequent in chronic biliary diseases such as hepatolithiasis 2,4. Patients with primary sclerosing cholangitis have a high risk of developing BilIN 2.
The concept of BilIN as a multistep cholangiocarcinogenesis has been proposed as the biliary counterpart for the pancreatic intraepithelial neoplasia (PanIN) 1,3.
BilINs are usually not visible on gross pathology specimens, eventually characterized as a subtle granularity of the mucosa 1.
These tumors show cellular atypia in the form of micropapillary projections into the bile ducts lumen (dysplastic epithelium). They are commonly identified within the mucosa adjacent to cholangiocarcinoma 1,2. Based on the architectural atypia, they are classified as 1,5:
- grade 1 BilIN: representing the low-grade lesions
- grade 2 BilIN: representing the intermediate-grade lesions
- grade 3 BilIN: representing the high-grade lesions, therefore, carcinoma in situ
Biliary intraepithelial neoplasia is not detected on imaging.
- 1. Argha Chatterjee, Camila Lopes Vendrami, Paul Nikolaidis, Pardeep K. Mittal, Andrew J. Bandy, Christine O. Menias, Nancy A. Hammond, Vahid Yaghmai, Guang-Yu Yang, Frank H. Miller. Uncommon Intraluminal Tumors of the Gallbladder and Biliary Tract: Spectrum of Imaging Appearances. (2019) RadioGraphics. 39 (2): 388-412. doi:10.1148/rg.2019180164 - Pubmed
- 2. Sanaz Ainechi, Hwajeong Lee. Updates on Precancerous Lesions of the Biliary Tract: Biliary Precancerous Lesion. (2016) Archives of Pathology & Laboratory Medicine. 140 (11): 1285-1289. doi:10.5858/arpa.2015-0396-RS - Pubmed
- 3. Sato, Yasunori, Harada, Kenichi, Sasaki, Motoko, Nakanuma, Yasuni. Histological Characterization of Biliary Intraepithelial Neoplasia with respect to Pancreatic Intraepithelial Neoplasia. (2019) International Journal of Hepatology. 2014: 678260. doi:10.1155/2014/678260 - Pubmed
- 4. World Health Organization, International Agency for Research on Cancer. WHO Classification of Tumours of the Digestive System. (2019)
- 5. Kun Jiang, Sameer Al-Diffalha, Barbara A. Centeno. Primary Liver Cancers—Part 1: Histopathology, Differential Diagnoses, and Risk Stratification. (2018) Cancer Control. 25 (1): 1073274817744625. doi:10.1177/1073274817744625 - Pubmed
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Gallbladder and biliary tract pathology
- congenital malformations and anatomical variances
- gallbladder inflammation
- bile ducts inflammation
- gallbladder wall abnormalities
- diffuse gallbladder wall thickening (differential)
- focal gallbladder wall thickening (differential)
- porcelain gallbladder
- gallbladder polyps
- gallbladder malignancy
- other gallbladder abnormalities
- bile ducts neoplasms