Short-Course Chemoradiotherapy Followed by Chemotherapy for the Treatment of Resectable Gastric Adenocarcinoma

Inclusion Criteria: * Eastern Cooperative Oncology Group (ECOG) performance status =\< 2 * Patients with a biopsy-confirmed diagnosis of adenocarcinoma of the stomach * No evidence of distant metastatic disease based on standard of care preoperative imaging evaluation * Evidence of T2 stage or greater primary tumor, or any T stage with node positive disease based on endoscopic ultrasound or standard of care imaging * Leukocytes \>= 3,000/ul * Absolute neutrophil count \>= 1,500/ul * Platelets \>= 60,000/UI * Glomerular filtration rate \>= 60 mL/min/1.73 m\^2. The estimated glomerular filtration rate (eGFR) is calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. The eGFR declines with age. eGFR \< 60 mL/min/1.73 m2 is considered as "decreased". This equation should only be used for patients 18 and older. According to the National Kidney Foundation's Kidney Disease Outcome Quality Initiative (KDOQI) classification and 2012 Kidney Disease Improving Global Outcomes (KDIGO) Clinical Practice Guideline, the stage of CKD should be categorized based on estimated GFR Exclusion Criteria: * Presence of metastatic disease on staging with standard of care imaging, with or without diagnostic laparoscopy. Subjects not able to undergo staging laparoscopy due to previous surgery will not be excluded from this trial, and the determination of absence of metastatic disease will be decided solely on imaging consistent with our current standard of care * Pa…