Yield of biliary stent cytology: Is it time to think lean?

Background and study aims During evaluation of pancreaticobiliary strictures, it is common practice to send biliary stents for cytologic analysis. However, in recent years, complementary tissue acquisition techniques ranging from cholangioscopy to fine-needle biopsy have improved the ability to acquire tissue and diagnose malignancy. Data are limited on the current diagnostic yield and cost effectiveness of biliary stent analysis. Patients and methods We performed a retrospective study of all pancreaticobiliary stents sent for analysis in a tertiary care academic medical center from June 2013 to September 2016. Patient demographics, stent information, and final diagnosis history were collected through chart review. Costs were determined using published reimbursement rates for Medicare. Results Two hundred thirty-one stents from 175 patients were sent for cytologic analysis during the study period. Of the 62 stents obtained from patients ultimately diagnosed with malignancy, only one (1.6 %) had positive cytology for malignant cells, while the others were acellular/non-diagnostic (2/62, 3.2 %), negative (48/62, 77.4 %), or atypical (11/62, 17.7 %). The sensitivity of stent cytology for diagnosis of malignancy was 1.6 % (1/62). No cases were identified in which stent cytology changed clinical management. From a payer perspective, the mean estimated cost for each stent cytologic analysis is greater than $ 70.00. Conclusions While stent cytologic analysis is a common clinical practice, the diagnostic yield and cost effectiveness of the practice must be reevaluated. With the rise of newer diagnostic technologies such as digital cholangioscopy and endoscopic ultrasound-guided fine-needle biopsy, it may be time to “think lean” and acknowledge a sunset for biliary stent cytology.