LONG-TERM OUTCOMES OF ENDOSCOPIC ULTRASOUND-GUIDED RADIOFREQUENCY ABLATION (EUS-RFA) FOR ADVANCED PANCREATIC AND PERIAMPULLARY ADENOCARCINOMA

BackgroundLong term prognosis for pancreatic adenocarcinoma (PDAC) remains especially poor with an overall 5-year survival rate less than 9%. Endoscopic ultrasound (EUS) guided RFA (EUS-RFA) is an emerging technology and limited data exist regarding long-term outcomes of EUS-RFA for PDAC. In addition to thermal-induced coagulative necrosis and tissue damage, radiofrequency ablation (RFA) has potential to stimulate the host’s antitumor immunity. The aim of this study is to report long-term outcomes of EUS-RFA for unresectable PDAC.MethodsRetrospective chart review of adult patients with an established diagnosis of locally-advanced or metastatic PDAC undergoing EUS-RFA between October 2016 to March 2018 with long term follow up (>30 months). Patients included in the review underwent a total of 1-4 RFA sessions using the Habib EUS-RFA radiofrequency catheter. All patients were concurrently undergoing standard of care chemotherapy.Results10 patients (median age 62 years, male 70%) underwent EUS-RFA (Table 1). Location of the primary PDAC was in the head (4), neck (2), body (2), and tail (2). A total of 22 RFA sessions were performed with a range of 1-4 RFA sessions per patient. RFA was technically successful in all RFA sessions (100%). There were no major adverse events (bleeding, perforation, infection, pancreatitis) in immediate (up to 72 hours) and short-term follow up (4 week). Mild worsening of existing abdominal pain was noted during post-procedure observation in 12/22 (55%) of RFA treatments. Follow-up imaging after RFA treatment was available in 8/10 patients. Tumor progression was noted in 2 patients, whereas tumor regression was noted in 6 patients (>50% reduction in size in 3 patients). Median survival for the cohort was 20.5 months (95% CI, 9.93 to 42.2 months). Currently, 2 patients remain alive at 53 and 73 months follow-up since initial diagnosis. One patient had 3 cm PDAC with encasement of the portal confluence, abutment of the celiac axis, common hepatic and superior mesenteric artery. This patient had significant reduction in tumor size and underwent standard pancreaticoduodenectomy.ConclusionIn our experience, EUS-RFA was safe, well-tolerated and could be concurrently performed with standard of care chemotherapy. In this select cohort, median survival (20.5 months) was improved when compared to published survival based upon SEER database and clinical trials. Future prospective trials are needed to understand the role of EUS-RFA in overall management of PDAC.