Methods The medical records of 133 patients with SMTs in the lesser curvature treated at Peking University First Hospital from January 2002 to December 2017 were retrospectively analyzed. Patients with other epithelial tumors, multiple tumors, and accidentally discovered SMTs during surgery were excluded. The clinical manifestations, preoperative diagnosis, tumor distribution, pathological features, surgical methods, and postoperative complications of SMTs in the lesser curvature were summarized. A retrospective cohort study was used to analyze the differences between gastrointestinal stromal tumor (GIST) and schwannoma in the above aspects.
Results A total of 133 patients were included, with an average age of (56.4±12.7) years, including 48 males and 85 females. The first conditions or symptoms were physical examination findings, abdominal pain, upper abdominal discomfort, melena, body mass loss, acid reflux, anemia, hematemesis, and pyloric obstruction. The preoperative diagnosis rates of gastroscopy combined with endoscopic ultrasonography (EUS) and abdominal CT were 78.7% and 68.8%, respectively. The surgical methods included endoscopic surgery in 10 cases, partial gastrectomy in 94 cases, subtotal gastrectomy in 21 cases, and total gastrectomy in 8 cases. The postoperative complication rate was 6.8%, with common complications including delayed gastric emptying, stenosis, anastomotic leakage, intestinal obstruction, and postoperative bleeding. The diagnosis rate of GIST (94.9%) was significantly higher than that of schwannoma (9.5%). The postoperative pathological types contained 98 cases of GIST (73.7%), 21 cases of schwannoma (15.8%), 6 cases of leiomyoma (4.5%), 6 cases of ectopic pancrea (4.5%), 1 case of lipoma (0.8%), and 1 case of bronchiogenic cyst (0.8%). Compared with the schwannoma group, the number of patients with preoperative hemoglobin concentrations<110 g/L and the preoperative diagnosis rate in the GIST group were significantly higher (P<0.05 and<0.01). There were no significant differences in age, gender, BMI, surgical procedure, distribution of tumor wall, growth direction, long diameter, infiltrating mucosa, subserosal invasion, or lymph node metastasis (P>0.05).
Conclusion Preoperative diagnosis rate of submucosal tumors in the lesser curvature is low, and GIST and schwannoma are more common pathological types. EUS is essential before operation. Surgical methods should be properly determined according to the tumor characteristics, location, and origin to prevent postoperative complications such as stenosis and delayed gastric emptying.