Zhang Y, Jiang Q, Wang Q, et al. - Correct discrimination between benign and malignant biliary stricture (MBS) is significant but challenging, therefore, this study provides a nomogram that is capable of predicting malignancy in patients whose endoscopy tissue diagnoses were non-malignant. Addition of nomogram improved overall diagnostic performance.

• This study involved 232 patients with suspected MBS who had endoscopy tissue sampling done; 123 patients’ endoscopy tissue samples were categorized as non-malignant (including atypical, negative for malignancy, and non-diagnostic).

• A nomogram was constructed based on bilirubin, carbohydrate antigen 19–9, radiological result, and atypical sampling findings and offered an area under the curve of 0.863 for predicting MBS.

• The specificity, sensitivity, and accuracy of endoscopy tissue diagnosis were reported to be 100.00%, 59.90%, and 68.53%, respectively.

• Addition of the nomogram provided overall diagnosis specificity, sensitivity, and accuracy of 95.24%, 89.20%, and 90.23%, respectively.