Proposal for a New Surgical Technique: Long Biliopancreatic Limb and Complete Duodenal Exclusion with Preservation of Pyloric Sphincter Function

Background: In non-obese patients with type 2 diabetes mellitus (T2DM), metabolic surgery is often limited by the unexpected inconsistent outcomes. Although pylorus-preserving gastric bypass procedures have been widely adopted, incomplete foregut exclusion frequently results in unsatisfactory glycemic control or relapse. To address this limitation, we propose Single Anastomosis Pyloro-Enterostomy (SAPE), designed to achieve complete duodenal exclusion while maintaining pyloric sphincter function. Methods: Based on long-term clinical observation and analysis of incretin dynamics, SAPE was developed as a loop-type single-anastomosis configuration incorporating a sufficiently long biliopancreatic (BP) limb. The duodenal tissue attached to the pyloric ring is completely removed, and the small intestine is anastomosed directly to the pylorus using interrupted sutures to preserve sphincteric motility. Anatomical design was guided by evidence from enteroendocrine physiology, epithelial-mesenchymal crosstalk, and reprogramming of regional intestinal identity after anastomosis. Results: Compared with pylorus-preserving duodenal-jejunal bypass (DJB) and other incomplete foregut-excluding procedures, SAPE theoretically enables more profound and durable suppression of a key diabetogenic signal originating from the proximal small intestine. The combination of complete duodenal exclusion and an adequately long BP limb minimizes the re-expansion of proximal epithelial identity and maintains long-term glycemic improvement without compromising digestive continuity or nutritional status. Conclusion: SAPE may provide a physiologically optimized surgical framework for the treatment of non-obese T2DM by integrating anatomical precision with metabolic efficacy. This technique ensures complete foregut exclusion, preserves pyloric function, and potentially prevents enteroendocrine reprogramming associated with late glycemic relapse. Further clinical evaluation is warranted to confirm its metabolic and functional outcomes.