The aim of this study is to identify a dysplasia- and CCA-specific NGS panel to increase the diagnostic sensitivity of histological and/or cytological examination of biliary tract stenosis.

Patients undergoing biliary tract resection, as part of the normal course of care, at the O.U. General Surgery and Transplantation will be enrolled. Tissue samples will be processed and analysed at the O.U. of Pathological Anatomy.

Clinical, serological and instrumental data from patients, considered necessary for the intended analyses, will be collected for the purposes of the study.

The study will have a total duration of 36 months. It is planned to enrol 50 patients, all belonging to the U.O. Hepatobiliary and Transplant Surgery of the IRCCS Azienda Ospedaliero-Universitaria di Bologna. The size of the population is estimated on the basis of the number of cases/year from the U.O. Hepatobiliary and Transplant Surgery, and is considered sufficient to achieve the primary objective, since it is an exploratory study. Surgical material (resection of biliary tract, possibly hepatectomy or duodenocephalopancreasectomy), which will be sampled according to clinical practice and sent to the O.U. of Pathological Anatomy of the IRCCS AOUBO, where it will be sampled, fixed in formalin, included in paraffin and processed. From paraffin blocks (selected from those obtained from the sampling of surgical pieces according to clinical practice) 2 µm sections will be cut for Next Generation Sequencing investigations.

Inclusion Criteria:

• Availability of enough tissue for histological and NGS analysis (at least 20 ng DNA).
• Age greater than/equal to 18 years.

Exclusion Criteria:

• None