Irinotecan and Cisplatin in Treating Patients Who Are Undergoing Surgery For Locally Advanced Cancer of the Stomach or Gastroesophageal Junction

Inclusion Criteria: * All patients must have microscopically confirmed adenocarcinoma of the stomach or gastroesophageal (GE) junction with material reviewed by the Department of Pathology of the participating Institution; tumors involving the GE junction must have the bulk of their disease in the stomach; tumors of the distal esophagus that extend less than 2cm into the stomach are ineligible for this study; using the Siewert's classification for the GE junction, tumors designated as Types II and III are indeed considered eligible for this clinical trial * All patients must have localized cancer potentially curable by surgery; the tumor stage should be Tany N+ M0 or T3-T4 Nany M0, by staging that includes a computed tomography (CT) scan and either laparoscopy-assisted pancreatobiliary (LAP) or endoscopic ultrasound (EUS); patients with T1-2N0M0 tumors, confirmed by LAP ("good risk") are ineligible; any sites of suspected M1 disease by these criteria must be proven to be M0 prior to entrance into a neoadjuvant trial * Patients must have a Karnofsky Performance Status \>= 60% (Eastern Cooperative Oncology Group \[ECOG\] =\< 2) and be able to tolerate the proposed surgical procedure and chemotherapy regimen * Patients may not have received prior chemotherapy or radiation for this disease * Absolute neutrophil count (ANC) \>= 1,500 cells/mm\^3 * Platelets \>= 100,000/mm\^3 * Serum creatinine =\< 1.5 mg/dL * Total serum bilirubin =\< 1.5 mg/dL * Patients must have signed informed consent indicating that they are aware of the investigational nature of the study and that participation is voluntary * No clinically significant auditory impairment * No clinically significant peripheral neuropathy * New York Heart Association (NYHA) class I-II * Patients must not have a prior history of cancer within the last five years except for non-melanoma skin cancer, non-metastatic prostate cancer or carcinoma in situ of the uterine cervix Exclusion Criteria: * Any metastatic disease * NYHA Class III or IV heart disease; history of active angina or myocardial infarction within 6 months; history of significant ventricular arrhythmia requiring medication with antiarrhythmics or a history of a clinically significant conduction system abnormality * Pregnant or lactating women are ineligible; fertile men and women, unless using effective contraception, are ineligible; a pregnancy test will be performed on sexually active women of childbearing potential prior to entry into the study; treatment may not begin until the results of the pregnancy test are ascertained * Serious intercurrent infections, or nonmalignant medical illnesses that are uncontrolled or whose control may be jeopardized by the complications of this therapy * Grade 2 or greater pre-existing peripheral neuropathy * Psychiatric disorders rendering patients incapable of complying with the requirements of the protocol * Any concurrent active malignancy other than non-melanoma skin cancers, non-metastatic prostate cancer or carcinoma-in-situ of the uterine cervix; patients with previous malignancies but without evidence of disease for \> 5 years will be allowed to enter the trial * Clinically significant hearing loss