Leveraging artificial intelligence to differentiate benign from malignant biliary strictures: A step toward precision diagnosis

Table 2 Endoscopic retrograde cholangiopancreatography-based sampling modalities

Baseline modality	Sensitivity and specificity range, %	Combined (with biopsy) sensitivity and specificity range, %	Incremental gain, %	Notes
Brush cytology alone[1,11,13,20-22]	Sensitivity 27-79. Specificity 90-100	Sensitivity 66-83.3. Specificity 95-100	Incremental 15-20 sensitivity over single methods	Data from retrospective cohort (Nanda et al[13] n = 61, CCA diagnosis including hilar, perihilar and distal strictures) and RCT comparing brush types (n = 64, extrahepatic strictures[21]). Data from systematic review and meta-analysis (16 studies); yield improves with multiple passes and bile cytology, RCT shows yield improves with modified biopsy forceps[20,22]
Brush cytology and FISH][1,13,23-26]	Sensitivity 35-84. Specificity 54.1-98	Sensitivity 70-82. Specificity 90-100	20-40 yield gain over cytology alone, highest ERCP yield (triple sampling), real-time risk stratification	Data from retrospective cohort (Nanda et al[13] n = 61, CCA diagnosis including hilar, perihilar, and distal strictures), comparative study by Kipp et al[23]. n = 131, including biliary strictures, data from prospective study, n = 81 with biliary and pancreatic duct strictures[24], data from retrospective study n = 614 patients[25], 10 years retrospective study of 281 patients[26]. FISH detects polysomy (aneuploidy) in 80% malignancies, misses diploid tumors, biopsy has no submucosal access

CCA: Cholangiocarcinoma; ERCP: Endoscopic retrograde cholangiopancreatography; RCT: Randomized control trial; FISH: Fluorescence in situ hybridization.