Improving the diagnostic yield of biliary stricture biopsies using a directional atherectomy device.

Abstract

e16167 Background: Diagnosing the pathologic etiology of biliary strictures presents challenges that have been well-documented. Accuracy of traditional brushing and fine needle aspirate techniques range from 44% to 73%.2 Over the last 2 decades the use of atherectomy catheter biliary biopsy has demonstrated high sensitivity and positive predictive values with a low complication rate. This endoluminal approach allows for larger volume histologic samples, allowing for the potential to obtain adequate tissue for next generation sequencing (NGS). The aim of this retrospective review of a single-center’s experience was to define the accuracy, ease of evaluation, and the ability to obtain NGS for personalized treatment. Methods: A retrospective review was performed under a waiver from the Institutional Review Board. A search of medical records from 1/2016 to 2/2021 yielded 20 biopsies in 19 patients. The 20 biopsies were completed by 4 interventional radiologists with between 2-11 years of experience. All available samples were analysed by a pathologist with greater than 10 years of experience and graded for adequacy and feasibility of NGS. Results: The patient population was 53% female with average age of 65.1 years. 12/19 (63%) patients had prior non-atherectomy biopsy attempts. The average ease of evaluation score for the 19 biopsies was 7.8/9, compared to 6.2/9 for the brushing specimens obtained from a subset of the same patients. Seven biopsies were positive for malignancy, ten were benign and three were non-diagnostic. The 7 biopsies that rendered a definitive diagnosis of malignancy had an average ease of evaluation score 8.7/9. The overall accuracy rate was 78.9%, and 71% of malignant samples were deemed adequate for NGS. There were two biopsy related complications; one pseudoaneurysm treated with embolization and one biliary drain dislodgement. Conclusions: Biliary biopsy using an atherectomy device has similar accuracy to traditional techniques; however, it allows for improved diagnostic yield and increased tissue specimen with 71% of samples adequate for NGS testing.