Peroral Cholangioscopy-Guided Forceps Biopsy and Endoscopic Scraper for the Diagnosis of Indeterminate Extrahepatic Biliary Stricture

Background: Peroral cholangioscopy (POCS) has become a widely-used technique in diagnosing indeterminate biliary strictures, enabling optical viewing of the biliary system and targeted biopsies under direct vision. The diagnostic utility of the new endoscopic scraper, Trefle(®), for extrahepatic cholangiocarcinoma (ECC) has also been reported. However, the diagnostic utility of POCS-guided and Trefle(®)-assisted tissue acquisition for ECC has never been compared empirically. We evaluated the efficacy and safety of Trefle(®)-assisted tissue acquisition for diagnosing ECC compared with POCS-guided tissue sampling. Methods: Patients who underwent Trefle(®)-assisted tissue acquisition or POCS-guided forceps biopsy to differentiate ECC from benign biliary disease between April 2014 and March 2018 were enrolled retrospectively. We evaluated the diagnostic performance of Trefle(®)-assisted tissue acquisition and POCS-guided forceps biopsy based on pathological evaluation. We also compared adverse events associated with Trefle(®)-assisted tissue acquisition with those of POCS-guided forceps biopsy. Results: We enrolled 34 patients with biliary disease and performed Trefle(®)-assisted tissue acquisition and POCS-guided forceps biopsy in 14 and 20 patients, respectively. Sensitivity, specificity, and accuracy of Trefle(®)-assisted tissue acquisition were 87.5%, 83.3%, and 85.7%, respectively, and for POCS-guided forceps biopsy, these were 90.0% each. Statistical values of Trefle(®)-assisted tissue acquisition and POCS-guided tissue acquisition were not significantly different. There were no significant differences in the occurrence of adverse events between the Trefle(®)-assisted tissue acquisition and the POCS-guided forceps biopsy (35.7% vs. 25.0%, p = 0.770). Compared with patients who underwent POCS procedure, endoscopic sphincterotomy was performed for fewer patients who underwent Trefle(®)-assisted tissue acquisition (p < 0.001). Conclusions: The diagnostic ability of Trefle(®)-assisted tissue acquisition for ECC is similar to that of POCS-guided tissue acquisition. Trefle(®)-assisted tissue acquisition might also help to preserve the sphincter of Oddi and its digestive function.