Sp603 Subepithelial Tumors: Just “FLUB” It! (Float-Ligate-Unroof-Biopsy)

Endoloop ligation has been previously reported for the treatment of subepithelial tumors. Miniprobe-EUS requires water submersion for acoustic coupling. In appropriately selected cases, EUS can be followed immediately by underwater looping. Water submersion may facilitate loop ligation due to a floating and contracting effect. Ligation strangulates off blood supply to the tumor, which leads to ischemic tumor ablation. Unroofing enables biopsies of the underlying tumor, but also promotes spontaneous tumor enucleation. Ligation prior to unroofing may reduce risks of bleeding and perforation, and ischemia contributes to tumor enucleation. The aim of our study was to evaluate the feasibility and outcomes of FLUB (Float-Ligate-Unroof-Biopsy) for the diagnosis and treatment of subepithelial tumors. EUS was performed with a 12 MHz radial-scanning catheter miniprobe inserted through a therapeutic channel gastroscope or colonoscope. A standard nylon endoloop (3 cm diameter) was used for loop ligation. A standard needle knife was used for unroofing. A standard biopsy forceps was used for subepithelial tumor sampling. We excluded patients with nonpedunculated tumors originating from the 4th wall layer (muscularis propria). Results: 17 patients (7 males) with a mean age of 67 underwent the FLUB procedure. Most lesions were incidentally found on endoscopy throughout the GI tract (Incidental -11; Bleeding - 2; Obstruction -2). Most lesions were lipomas, but there were other diagnoses (Histology: Lipoma -11; Carcinoid -2; Granular cell -1; Leiomyoma - 1; Hamartoma-1; Vanek's tumor -1). Median size was 15mm (range: 4-55). There were no complications, including no intraprocedural bleeding. Follow-up: available in 8 patients (47%), of whom 3 (37%) had residual lesions that were all relooped. Conclusion: 1. Underwater loop ligation of subepithelial tumors can be performed seamlessly after EUS. 2. Water facilitates loop ligation of subepithelial tumors. 3. The FLUB technique simplifies the diagnosis and therapy of subepithelial tumors.