Local Thymosin β4 Gel Injection Prevents Esophageal Stricture after Circumferential Endoscopic Submucosal Dissection in a Porcine Model

Background: Endoscopic submucosal dissection (ESD) is widely used in the treatment of early esophageal cancer. However, the incidence of postoperative esophageal stricture is relatively high, especially after full circumferential ESD. Previous studies have shown that thymosin β4 (Tβ4) has anti-fibrotic activity and prevents scar formation. In this study, we investigated the safety and therapeutic effect of Tβ4 injection in preventing esophageal stricture after circumferential ESD in a porcine model. Methods: A total of 8 Bama pigs underwent esophageal circumferential ESD under anesthesia (n = 4 for experimental and control group). Local injection of Tβ4 gel was administered in the experimental group. Follow-up endoscopy was conducted, and balloon dilation (EBD) was performed to prevent the occurrence of esophageal stricture. Results: Esophageal stricture developed after circumferential ESD in all pigs. Local Tβ4 gel injection has shortened resolution of the stricture (p = 0.012) and was associated with a lesser number of EBD sessions (p = 0.002). The severity of esophageal stricture was milder in the experimental group (p = 0.046 vs. control group). No adverse events occurred in the study. Conclusions: Local Tβ4 gel injection appeared to be safe and effective for the prevention of esophageal stricture after circumferential ESD in a porcine model.