Comparison of the clinicopathological features between synchronous multiple early gastric cancer and single early gastric cancer

Objective To investigate the clinicopathological features and correlation between synchronous multiple early gastric cancer(SMEGC)and single early gastric cancer (EGC). Methods From January 2008 to December 2016, the clinical data of 994 patients with EGC who underwent open or laparoscopic gastrectomy surgery were collected from the electronic medical data base of the First Affiliated Hospital of Nanjing Medical University and Xuzhou No.1 People′s Hospital. The data of patients including gender, age, tumor morphologys, tumor location, tumor size, histological type, depth of invasion, lymph nodes metastasis, lymphovascular metastasis, peripheral nerve invasion, and blood types were analyzed. T test and Chi square test were used for statistical analysis. Results Among 994 EGC patients, 27 cases (2.7%) were SMEGC, and 967 cases (97.3%) were single EGC. The percentage of male and female of single EGC were 71.4% (690/967) and 28.6% (277/967), respectively; the percentage of male and female of SMEGC were 88.9% (24/27) and 11.1%(3/27), respectively, and there was statistically significant difference in the gender composition ratio between single EGC and SMEGC (χ2=3.975, P=0.046). The incidence of ulcer in single EGC and SMEGC were 50.6% (489/967) and 29.6% (8/27), respectively, and the difference in the incidence of ulcers between single EGC and SMEGC was statistically significant (χ2=4.653, P=0.031). There were no statistically significant differences between single EGC and SMEGC in gross morphology, depth of invasion, lymph nodes metastasis, lymphovascular metastasis, peripheral nerve invasion, tumor location, pathological type and blood types (all P>0.05). In the SMEGC patients, the incidence of main lesions invading the mucosa was 48.1% (13/27) and submucosa invasion was 51.9% (14/27); and for minor lesions, the corresponding incidences were 77.8% (21/27) and 22.2% (6/27), respectively, and the difference was statistically significant (χ2=5.063, P 0.05). Conclusions The main risk factors of SMEGC are male and no ulcerative lesions. The clinicopathological features are similar between main lesions and minor lesions in SMEGC. Key words: Synchronous multiple early gastric cancer; Main lesions; Minor lesions; Clinicopathological features