Differential diagnosis of indeterminate bile duct strictures using peroral cholangioscopy

Introduction. Differential diagnosis of indeterminate biliary strictures is necessary for adequate planning of the treatment, which affects prognosis and helps to avoid unnecessary surgical interventions in patients with benign biliary strictures. Despite technological advances, the diagnostic accuracy of methods for the diagnosis of malignant lesions remains insufficient.Direct visualization of the biliary tree using peroral cholangioscopy may improve the ability to diagnose indeterminate biliary strictures.Aim. To investigate sensitivity and specificity of peroral cholangioscopy in the diagnosis of indeterminate biliary strictures.Materials and methods. A retrospective review of the patient database of the N. N. Blokhin National Medical Research Center of Oncology was conducted for the period from January 2022 to May 2024. Twenty-seven patients with indeterminate bile duct strictures were included in the study. After direct visualisation of the bile duct system, macroscopic tissue changes were determined and samples were taken for biopsy with SpyBite (Boston Scientific, USA) forceps.Results. SpyGlass (Boston Scientific, USA) visual impression accuracy was 87.6 %, sensitivity – 80.0 %, negative predictive value – 88.9 %, specificity and positive predictive value – 94.11 and 88.9 % respectively. SpyBite forceps biopsy results had a specificity and positive predictive value of 100 % but sensitivity and negative predictive value of 54.5 and 76.2 % respectively.Conclusion. Peroral cholangioscopy is an effective option in the differential diagnosis of indeterminate biliary strictures.