AIM: To evaluate the timing of chemotherapy in gastric cancer by comparing survival outcomes in treatment groups. METHODS: Patients with surgically resected gastric adenocarcinoma from 1988 to 2006 were identified from the Los Angeles County Cancer Surveillance Program. To evaluate the population most likely to receive and/or benefit from adjunct chemotherapy, inclusion criteria consisted of Stage Ⅱ or Ⅲ gastric cancer patients > 18 years of age who underwent curative-intentsurgical resection. Patients were categorized into three groups according to the receipt of chemotherapy:(1) no chemotherapy;(2) preoperative chemotherapy; or(3) postoperative chemotherapy. Clinical and pathologic characteristics were compared across the different treatment arms.RESULTS: Of 1518 patients with surgically resected gastric cancer, 327(21.5%) received perioperative chemotherapy. The majority of these 327 patients were male(68%) with a mean age of 61.5 years; and they were significantly younger than non-chemotherapy patients(mean age, 70.7; P < 0.001). Most patients had tumors frequently located in the distal stomach(34.5%). Preoperative chemotherapy was administered to 11.3% of patients(n = 37) and postoperative therapy to 88.7% of patients(n = 290). An overall survival benefit according to timing of chemotherapy was not observed on univariate or multivariate analysis. Similar results were observed with stagespecific survival analyses(5-year overall survival: Stage Ⅱ, 25% vs 30%, respectively; Stage Ⅲ, 14% vs 11%, respectively). Therefore, our results do not identify a survival advantage for specific timing of chemotherapy in locally advanced gastric cancer. CONCLUSION: This study supports the implementation of a randomized trial comparing the timing of perioperative therapy in patients with locally advanced gastric cancer. AIM: To evaluate the timing of chemotherapy in gastric cancer by comparing survival outcomes in treatment groups. METHODS: Patients with surgically resected gastric adenocarcinoma from 1988 to 2006 were identified from the Los Angeles County Cancer Surveillance Program. To evaluate the population most likely to receive and / or benefit from adjunct chemotherapy, inclusion criteria consisted of Stage II or III gastric cancer patients> 18 years of age who underwent curative-intentsurgical resection. Patients were categorized into three groups according to the receipt of chemotherapy: (1) no chemotherapy; (2) preoperative chemotherapy; or (3) postoperative chemotherapy. Clinical and pathologic characteristics were compared across the different treatment arms .RESULTS: Of 1518 patients with surgically resected gastric cancer, 327 (21.5%) received perioperative chemotherapy. patients were male (68%) with a mean age of 61.5 years; and they were significantly younger than Most patients had tumors frequently located in the distal stomach (34.5%). Preoperative chemotherapy was administered to 11.3% of patients (n = 37) and postoperative therapy to 88.7% of patients (n = 290). An overall survival benefit according to timing of chemotherapy was not observed on univariate or multivariate analysis. Similar results were observed with uncorrected survival analyzes (5-year overall survival: Stage II, 25% vs 30% respectively; Stage III, 14% vs 11%, respectively). CONCLUSION: This study supports the implementation of a randomized trial comparing the timing of perioperative therapy in patients with locally advanced gastric cancer.