BACKGROUND AND AIMS: Endoscopic full-thickness resection (EFTR) is still challenging, and a reliable technique is desirable. The aim of this study was to evaluate the feasibility of controlled EFTR using a pseudopolyp made from suture loop needle T-tag (SLNT) tissue anchors in ex vivo porcine stomachs. METHODS: Five pig stomachs were used. Two concentric circumferential border mucosal incisions were made to facilitate isolating a target lesion for full-thickness excision and pseudopolyp formation. SLNT tissue anchors were placed with a fishing line around the edges of the larger outer incision by endoscopic suturing. A suture pulley was created in the center of the targeted area and brought outside for traction. A large inverted pseudopolyp of the targeted lesion was made, visualizing apposing serosa with traction on the suture pulley while simultaneously cinching the encircling fishing line. EFTR was then performed on the isolated targeted tissue with the use of a needle-knife. RESULTS: Pseudopolyps were successful in all attempts. In the first attempt the encircling fishing line was cut, releasing the pseudopolyp during EFTR, with obvious leak. The remaining 4 EFTRs were performed with intact serosal apposing pseudopolyps and no air leaks. The median number of SLNT tissue anchors placed for a pseudopolyp was 5 (interquartile range, 4-5). The median size of full-thickness lesions was 37 mm (interquartile range, 29-49) and the median maximum pressure for the leak testing 9 mm Hg (interquartile range, 4-14) in the successful 4 attempts. CONCLUSION: This proof of principle study suggests that EFTR with SLNT-fashioned pseudopolyps is feasible.