Lightening up the Tunnel of Darkness: Endoscopic Radio Frequency Ablation of Malignant Biliary Stricture: A Novel Technique

Abstract

INTRODUCTION: Radio frequency ablation (RFA) role is established in the treatment of solid tumors. However, its application in biliary system is novel. A novel endoscopic RFA (ERFA) device is available now to manage malignant biliary obstruction (MBO). We are presenting our experience with this novel device. CASE PRESENTATION: Case is a 79 year old male with diagnosis of incidental gallbladder adenocarcinoma (stage IIB;T2bNxM0) after cholecystectomy for symptomatic cholelithiasis. He refused further work up and returned three months later with obstructive jaundice. Imaging showed biliary outflow tract obstruction. ERCP showed bilateral 2.5cm long right and left hepatic duct strictures (RLHDS) extending to common hepatic duct (CHD). Brushing and biopsies were negative. Two plastic biliary stent were placed in hepatic ducts. One month later, jaundice had resolved, nevertheless due to abdominal pain and suspicion for malignant biliary stricture (BS), ERFA of BS and placement of uncovered self-expanding metallic stents (USEMS) was planned for palliative care. ERCP with cholangioscopy confirmed RLHDS biliary strictures. The novel ERFA catheter with 8 F bipolar probe and two ring electrodes (8 mm long and 6 mm apart), providing local coagulative necrosis over a length of 25mm ± 3mm was advanced over the guidewire under fluoroscopic guidance to the hepatic duct stricture. Total 6 RFA ablations (bipolar energy of 7-10 watts above and below the bifurcation respectively; 90 seconds ablation time, 1 minute stability time) were performed sequentially in RLHDS and in CHD successfully. Post RFA, successful biliary ablation appearance and improved lumen patency was noted. Two novel laser cut USEMS with simultaneous deployment device were placed in right and left hepatic ducts with excellent bile drainage. DISCUSSION: USEMS has application in MBO. However, tissue in growth remains a challenge. ERFA before stent placement can delay tumor ingrowth and frequency of re-intervention. Potential complications include thermal injury followed by late bile leak, duodenal leak, or late bleeding. However, a recent clinical trial with 65 patients by Jianfeng Yang etal showed ERFA combined with stenting can significantly prolong survival and stent patency period without increase in adverse events. Large-scale, prospective multicenter trial with a long-term follow-up may reinforce the benefits of RFA on stent patency and survival rates.1412_A.tif Figure 1: Cholangiocarcinoma with biliary stricture prior to RFA1412_B.tif Figure 2: Biliary image post RFA ablation