Supplementary Material for: Glomus tumor of the stomach: a systematic review and illustrative case report

Introduction Glomus tumor is a rare mesenchymal neoplasm that can be found anywhere throughout the body, includ-ing the stomach. Our goal was to present a case and a systematic review of the literature, reporting clinical, radiological, surgical, and pathological features of the disease. Methods We reviewed Pubmed and SCOPUS for all case reports and case series published after 2000. Papers written in languages different from English and letters to the editor were excluded. Screening and data extraction were performed following the PRISMA guidelines. Results A total of 89 studies were included in the systematic review, consisting of 187 cases of gastric glomus tu-mor. Mean age was 52(18-90), most patients were female(61%). The most common clinical presentation was epigastric pain(33.9% of cases). Gastric antrum was the most frequently involved site (75.3%). Mean tumor size was 2.82 cm 0.8-17). Preoperative diagnosis was achieved in 22 cases, mostly by EUS-guided biopsy. Wedge resection was performed in 62% of treated patients. Smooth muscle actin was expressed in all cases with available immunohistochemistry. Malignant GT was reported in 11 cases. Discussion Epigastric pain and bleeding were the most common symptoms at presentation in patients with diagnosis of glomus tumor. EUS-guided fine needle aspiration can be useful for preoperative diagnosis. Endoscopic elastosonography is a promising tool for the differential diagnosis of gastric submucosal lesions, including glomus tumors. Treatment of choice is wedge resection with adequate free margins. Laparoscopic ap-proach is warranted when technically feasible. Since malignant gastric glomus tumors have been de-scribed, long term follow-up is suggested after surgical excision.