Effectiveness of cholangioscopy using narrow band imaging for hepatobiliary malignancies

Recently, cholangioscopy using narrow band imaging (NBI) has been used as a diagnostic modality for better visualization in hepatobiliary malignancies; however, there are few reports on it. Our aim is to evaluate the effectiveness of cholangioscopy using NBI in hepatobiliary malignancies.

Between January 2007 and December 2016, 152 cholangioscopies using percutaneous approach were conducted in total 123 patients. Among these, 36 patients were suspicious of hepatobiliary malignancies. Thirteen patients with an ambiguous margin on endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP), for whom NBI tipped the balance in diagnosis of lesion and decision of lesion extent by adding NBI, were involved in our study.

Underlying diseases were all malignant in 13 patients (11 bile duct cancers, 1 liver cancer, 1 pancreas cancer with common bile duct invasion). In 7 cases with papillary type tumor, minute superficial spreading tumor was detected by NBI more easily, and NBI provided a better visualization of tumor vessel and margin evaluation in 4 cases with infiltrative tumor. In 2 cases with mucin-hypersecreting tumor, NBI showed better penetration through the mucin and gave us a much clearer image. Nine patients ultimately underwent surgical resection. The margins predicted by NBI cholangioscopy were consistent with the pathological margins on the resected specimens.

In conclusion, cholangioscopy using NBI is very useful for evaluation of suspected hepatobiliary malignancies with an ambiguous margin on ERCP or MRCP. It can give us an accurate pathologic mapping, and this information seems to be essential before deciding on a treatment strategy.