Intraductal aspiration: a promising new tissue-sampling technique for the diagnosis of suspected malignant biliary strictures

Abstract

Background: Brushing is the most commonly used technique for biliary sampling at ERCP, despite its limited sensitivity.

Objective: To evaluate intraductal aspiration (IDA) as a new combined endoscopic technique for cytodiagnosis, its cellular adequacy, diagnostic accuracy for cancer detection, feasibility, and safety.

Design: Prospective, observational study.

Setting: Single tertiary referral center.

Main outcome measurements: IDA cellular adequacy, diagnostic accuracy for cancer detection, feasibility, and safety.

Patients and methods: From April 2009 to September 2010, 42 consecutive patients with suspected malignant biliary stricture underwent ERCP, with tissue sampling obtained with IDA. IDA included performance of standard brushing in all patients. After standard brushing, to perform IDA, we removed the brush from its catheter and used the tip of the catheter as a scraping device. The tip was scraped back and forth across the stricture at least 10 times. The catheter and a suction line were connected to a specimen trap to obtain intraductal aspiration of fluids and samplings.

Results: Our cytopathologists found adequate cellular yield in 39 of the 42 IDA samples (92.8%) versus 15 of the 42 brushing samples (35.7%) (P < .001). IDA showed a significantly higher sensitivity than brushing (89% vs 78% for adequate samples and 89% vs 37% for all samples) and provided significantly superior cellular adequacy (92.8% vs 35.7%).

Limitations: Observational study, small number of patients.

Conclusions: IDA significantly improves brushing cellular adequacy and has high sensitivity for cancer detection. It was also safe, simple, rapid, and applicable during routine diagnostic ERCP, with no additional costs.