BACKGROUND Gastrointestinal subepithelial tumors (GSTs), incidentally detected during upper gastrointestinal (GI) endoscopy, may be lesions derived from the GI wall or may be caused by compression from external organs. In general, traumatic neuroma is a benign nerve tumor that results from postoperative nerve injury, occurring in the bile duct as one of the complications after cholecystectomy. This is the first case report demonstrating that neuroma of the cystic duct can be incorrectly perceived as a duodenal subepithelial tumor by compressing the duodenal wall. CASE SUMMARY We report the case of a 72-year-old man with traumatic neuroma of the cystic duct after cholecystectomy. This tumor was mistaken for a duodenal subepithelial tumor on preoperative upper GI endoscopy and endoscopic ultrasonography due to external compression of the GI wall. The patient had no symptoms, and his laboratory test results were normal. However, in a series of follow-up endoscopies, the tumor was found to have grown in size, so it was surgically resected. The lesion was completely removed by laparoscopic endoscopic cooperative surgery. The patient was discharged on postoperative day 7 without complications. CONCLUSION Traumatic neuroma of the cystic duct can be mistaken for GSTs in GI endoscopy.

Purpose A novel resection method, namely, laparoscopic local resection through subserosal dissection with endoscopic air-insuff lation (LRSDEA) was used for submucosal tumors located near the esophagogastric junction (SMT-EGJ) to avoid major gastric resection. Methods A total of 9 cases underwent LRSDEA. We sequentially performed: laparoscopic dissections around EGJ, subserosal dissections around SMTs using laparoscopic electrocautery and ultrasonic shears, and finally, enucleation of SMTs. During these procedures, intraoperative endoscopic tumor localization, as well as endoscopic air-insufflation allowed for safe resection. These procedures are shown in the supplementary video clip. The clinicopathological characteristics and surgical results were analyzed. Results All laparoscopic procedures were successfully performed without requiring a major gastrectomy. The mean operation time was 126.1 minutes, and estimated blood loss was 12.0 ml. There were no postoperative complications. Pathological diagnoses were 6 leiomyomas, 2 gastrointestinal stromal tumors, and 1 gastric duplication. Conclusion LRSDEA is an effective and safe treatment option for SMT-EGJ, as major resection of the stomach is avoided.