['This study aimed to determine whether postoperative morbidity and mortality rates increased after preoperative chemoradiation in patients who underwent gastrectomy.', 'The medical records of 7404 patients with gastric or gastroesophageal cancer seen from January 1995 to August 2012 were reviewed to identify patients who underwent gastrectomy. χ (2) and logistic regression analysis were used to determine differences in the 90-day postoperative morbidity and mortality rates of patients who underwent upfront surgery (SURG), preoperative chemotherapy (CHEMO), or preoperative chemoradiation (CHEMOXRT).', 'Of the 500 patients included in this study, 200 underwent SURG, 65 had CHEMO, and 235 had CHEMOXRT. Respectively, 33, 43, and 58 % of these patients underwent total gastrectomy (p < 0.01). Resection of other organs was performed respectively in 19, 26, and 23 % of the patients (p = 0.37). Minor complications within 90 days (Clavien-Dindo 1 or 2) occurred for 41 % of the SURG patients, 43 % of the CHEMO patients, and 45 % of the CHEMOXRT patients (p = 0.68). Major complications or death within 90 days (Clavien-Dindo 3, 4, or 5) occurred for 21, 28, and 29 % of the patients, respectively (p = 0.15). The 90-day mortality (Clavien-Dindo 5) rates were 2 % for the SURG patients, 6 % for the CHEMO patients, and 3 % for the CHEMOXRT patients (p = 0.25). The median hospital stays were respectively 12, 12, and 13 days (p = 0.09). In the multivariate analysis, male sex, gastroesophageal junction cancer, total gastrectomy, and resection of other organs were associated with increased major morbidity and mortality rates, whereas preoperative therapy was not.'] Are postoperative Morbidity and Mortality Rates Increased for Patients with Gastric and Gastroesophageal Cancer Who Undergo Preoperative Chemoradiation Therapy?