Tehran University of Medical Sciences Basic & Clinical Cancer Research 2228-6527 14 2 2023 06 17 78 86 Ali Farahat Yazd University of medical science Amirhossein Emami Department of Hematology and Oncology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran Seyed Reza Safaei Nodehi Department of Hematology and Oncology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran Kamran Roudini Department of Hematology and Oncology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Farhad Shahi Department of Hematology and Oncology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. 2022 01 30 2023 01 11 Abstract Objective: We aimed to investigate safety and efficacy of preoperative chemotherapy using EOX regime in patients with locally advanced gastric and GEJ cancer who were admitted at Imam-Khomeini Oncology clinic and Aram clinic. Method: We performed a mix-cohort study in 51 gastric cancer patients. In the beginning, we performed contrast thorax and abdominal CT scan or ECO cardiograph to determine cancer staging. After that, each patient received 3-weeks EOX regime in 6 cycle. After each three cycles follow-up CT scan was performed to assess any possible progression. Response to the treatment, Overall survival, and Progression-Free Survival were the main outcomes that we evaluated in the current study. We used Kaplan-Meier approach and Cox regression to address survival rate and its prognostic factors. Results: Overall, 72.5% percent were male and mean age of study participants was 57.6. Complete response rate was observed in 11.1%, while 51.1% showed partial response. Median of overall survival and Progression-Free Survival was estimated 35.0 and 28.0 month, respectively. The 5-year overall survival was 74.2% and for PFS it was estimated at 57.7%. Conclusion: Preoperative chemotherapy using EOX regime could increase survival rate among patients with gastric and GEJ cancer. https://bccr.tums.ac.ir/index.php/bccrj/article/view/414