ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY (ERCP) FOR CHRONIC MANAGEMENT OF BILIARY INTRAEPITHELIAL NEOPLASM (BILIN)

Introduction:
Biliary intraepithelial neoplasm (BilIN) and intraductal papillary neoplasm of the bile duct (IPNB) are two pre-invasive neoplasms that can lead to cholangiocarcinoma (CCA)¹. IPNB has a high tendency to present with high-grade dysplasia (HGD), and invasive lesions¹. For BilIN and IPNB, early, surgical resection remains the most recognized method of preventing disease progression¹. However, we present a case of a patient with BilIN, not amenable to surgery in which endoscopic retrograde cholangiopancreatography (ERCP) guided resection and radiofrequency ablation (RFA) led to a disease-free state.

Case Presentation:
A 71-year-old old female was evaluated for persistent right upper quadrant pain with magnetic resonance cholangiopancreatography (MRCP) with findings significant for intra- and extra-hepatic ductal dilation. Initial ERCP demonstrated a polyp found during balloon sweep with biopsy revealing BilIN. She was referred to our comprehensive cancer center for repeat surgery, which she declined. Her case was discussed at a multidisciplinary tumor board and ERCP was performed with the hope of resection and potential RFA of this BilIN. For the second ERCP, a cholangiogram revealed a 10mm stenosis at the lower third of the main bile duct (BD). After a second balloon sweep to remove mucin, stones and eventually a frond-like villous polyp with surrounding villiform mucosa at the lower third of the BD. Cholangioscopy was performed and brushing/biopsies obtained throughout the entire biliary tree for mapping. The polypoid area was then swept outside the papillary orifice, and completely resected using a snare. The polypectomy specimen and lower third BD confirmed HGD-BilIN. A third and fourth ERCP was performed after 3- and 6-months revealing stenosis which after biopsy was ablated via RFA. Biopsy were negative for dysplasia or malignancy. The patient has additionally undergone a 1-year follow-up at an outside institution and biopsies remain without BillN. The patient remains in close follow-up between our centers including biomarkers, imaging, and endoscopic evaluations.

Conclusions:
Although surgery is the definitive treatment for BillN and IPNB, this case highlights a teaching point regarding the challenge of managing a rare diagnosis with unclear guidelines and patient desire to withhold surgery.

References
1.Nakanuma Y, Uesaka K, Kakuda Y, et al. Intraductal Papillary Neoplasm of Bile Duct: Updated Clinicopathological Characteristics and Molecular and Genetic Alterations. J Clin Med. 2020;9(12):3991.