Endoscopic transmural route for dissection of gastric submucosal tumors with extraluminal growth: experience in two cases.

The spectrum of endoscopic resection methods, including full thickness techniques, has enabled removal of most smaller gastric submucosal tumours (SMTs). We developed an extended transmural endoscopic dissection technique for lesions with predominately extraluminal growth arising from the muscularis propria. It consists of transmural intraperitoneal access with the endoscope besides the lesion followed by subserosal dissection from the outside. The technique was successful in two patients with smaller (2–3 cm) gastric stromal tumours; lesions were resected completely and short-term follow-up was normal. Further studies are warranted to confirm the safety and feasibility of this this new approach. With the popularisation of endoscopy and the development of endoscopic ultrasonography (EUS), the detection rate of gastrointestinal (GI) SMT has increased significantly.1 Complete surgical resection is still recognised as the primary and the most important way to treat gastric SMT and to get clear pathological diagnosis.2 Minimally invasive endoscopic therapy received increasing recognition due to its advantages of less invasiveness, fewer complications, quicker recovery and lower costs compared with open surgery or laparoscopic surgery. Gastric SMTs derived from mucosal and submucosal layers could be resected by endoscopic mucosal resection and endoscopic submucosal dissection, while those originated from deep layers of the gastric wall can be resected using endoscopic full-thickness resection (EFTR), which intentionally perforates the gastric wall to achieve complete resection.3 With an increasing emphasis on protecting the intact of mucosa, endoscopic mucosa-sparing lateral dissection was developed to reduce the postoperative complications.4 Inspired by the submucosal tunnelling endoscopic resection (STER)5 technique, in which maintenance of mucosal integrity and the longitudinal submucosal tunnel lead to rapid healing and decreased risk of pleural infection, STER for extraluminal tumours was reported for resection of SMTs with a predominant extraluminal growth pattern or extra-GI tumours.6 However, for most SMTs with a predominately extraluminal …