Endoscopic Ultrasound-Guided Radiofrequency Ablation as an Future Alternative to Pancreatectomy for Pancreatic Metastases from Renal Cell Carcinoma: A Prospective Study

SIMPLE SUMMARY: Glandular metastases and more precisely pancreatic metastases (PM) from renal cell carcinoma (mRCC) are associated with a long survival. Focal treatment in order to control oligo-metastatic disease and avoid systemic therapy is a standard in RCC. However, pancreatic radiofrequency ablation remains a marginal and under evaluated technic. Standard treatment remains pancreatectomy with hazardous outcomes. We report here the largest series of endoscopic radiofrequency ablation (EUS-RFA) on PM for patient treated at Institut Paoli-Calmettes for a mRCC. Patients with progressive PM was treated under general anesthesia with an ultrasound guided endoscopic radiofrequency ablation procedure then followed by CT-scan. We prospectively included 12 patients, median age was 70.5 years old and median size and number of PM at inclusion was 17 mm and 1 respectively. All 26 procedures performed went as planned and no immediate complications were experienced. After 27.7 months of follow-up, the 6- and 12-month focal control rates were 84% and 73% respectively. Two severe complications occurred after EUS-RFA but were totally resolved after specific treatment. In total, EUS-RFA is feasible and displayed an excellent focal control and should be integrated in the arsenal to treat PM from mRCC in order to spare systemic therapy and/or pancreatic surgery. ABSTRACT: Background: Pancreatic metastases (PM) from renal cell carcinoma (RCC) are rare, are associated with favorable outcomes and are usually handled by surgery or VEGFR inhibitors, which both have side effects. Endoscopic Ultrasound (EUS)-guided radiofrequency ablation (RFA) is an innovative approach to treat focally deep metastases and could be a relevant technique to control PM from RCC. Methods: This monocentric, prospective study aimed to evaluate the safety and efficacy of EUS-RFA to treat PM. We included patients with confirmed and progressive PM from RCC. PM was ablated under general anesthesia with a linear EUS scope and a EUS-RFA 19-gauge needle electrode placed into the tumor. Results: Twelve patients from Paoli-Calmettes Institute were recruited between May 2017 and December 2019. Median age was 70.5 years (range 61–75), 50% were female, 100% were ECOG 0–1. At inclusion, mean PM size was 17 mm (range 3–35 mm); and all were progressive before EUS-RFA. Seven patients had EUS-RFA as the only treatment for RCC. We performed 26 EUS-RFA procedures and 21 PM was ablated. Median follow up was 27.7 months (range 6.4–57.1). For evaluable PM, the 6- and 12-month focal control rates were 84% and 73% respectively. One patient treated with TKI developed a paraduodenal abscess 2 months after EUS-RFA and another patient with biliary stent developed hepatic abscesses few days after EUS-RFA. No other severe side effects were experienced. Conclusions: in this series, which is the largest ever reported, we showed that EUS-RFA is feasible and yields an excellent local control rate for PM from mRCC. With manageable complications, it could be a valuable alternative to pancreatic surgery in well-selected patients.