Endoscopic submucosal dissection for the diagnosis and treatment of a gastric submucosal tumor: initial experience in Greece
A 78-year-old woman with a history of right heart failure on anticoagulant therapy was referred to our department due to persistent dyspeptic symptoms. Upper gastrointestinal (GI) endoscopy revealed a submucosal lesion, ulcerated on top, measuring approximately 35 mm × 10 mm, on the anterior-inferior wall of the antrum (). Boring biopsies were obtained. Endoscopic ultrasonography revealed a well-circumscribed homogenous, hypoechoic mass 35 mm × 12 mm in size originating from the second gastric wall layer – muscularis mucosa (). Pathologic examination proved insufficient to provide a definitive diagnosis, setting the differential diagnosis among PDGFRA(+) GIST, leiomyoma and leiomyosarcoma. Immunohistochemistry revealed SMA(+), suggestive of a leiomyoma/leiomyosarcoma although desmin(-) and CD34(+), suggestive of GI stromal tumor although CD117(c-kit) (-). Moreover S-100 was negative, excluding tumors of neural origin and Schwannoma. Since the patient was not an eligible surgical candidate due to comorbidities and advanced age, she was referred for ESD after obtaining informed consent.\nMidazolam plus propofol were used for sedation under anesthesiological supervision. A triangle-tip electrocautery knife (TT-Knife, KD-640L; Olympus Optical) was used through a standard-size video endoscope (GIF-1T140; Olympus Optical). A soft transparent straight-type cap device (MH595; Olympus Optical) was attached to the tip of the endoscope to obtain proper direct views of the submucosal layer.\nResection of the submucosal lesion was performed according to the previously published experience [,]. Initially, the demarcation of the marginal dissection line was performed, approximately 5 mm distant from the tumor margin, by applying argon plasma coagulation (35W, 0.8 L/min) using a 2.3 mm diameter probe (APC-Sonde 2200 A; ERBE Elektromedizin GmbH). Complete lift of the lesion was achieved by submucosal injection of a solution of 0.5 mL of epinephrine 0.1% added in 100 mL Glycerol with 1 mL indigo carmine dye. Additional submucosal injections of epinephrine solution were applied to maintain the lift effect, when needed. Exposed blood vessels of the ulcer bed were thoroughly coagulated either with the bottom of the triangular plate or using hemostatic forceps (Coagrasper, Olympus Optical), to prevent bleeding. Finally, the resection site was carefully observed to evaluate the presence of any residual tumor and sucralfate was sprayed onto the ulcer (). The duration of the procedure was 55 min, consistent with the published data, while no immediate complications, such as perforation or postoperative bleeding, occurred.\nAfter complete en bloc resection, tissue specimen was fixed along its edges using thin needles, inserted onto a wooden plate and fixed in formalin solution. Histopathology examination confirmed complete resection and set the diagnosis of leiomyoma.\nUpper GI endoscopy was carried out six days after the procedure in order to evaluate the ulcer bed and to initiate per os anticoagulation therapy (). Follow-up upper GI endoscopy 3 months later did not reveal any signs of recurrence.