Inclusion Criteria: 

• Age ≥18 and ≤ 80 years

• Disease characteristics

• Histological confirmation of adenocarcinoma of the stomach or gastroesophageal junction (GEJ) (Siewert type II or III)

• Tumor index (TI) ≥90 (T stage multiplied by the largest tumor diameter in mm on EUS).  Patients with linitus plastica automatically have TI ≥90.

• The following laboratory values obtained ≤30 days prior to registration:

• • Hemoglobin ≥8.0 g/dL
  • Absolute neutrophil count (ANC) ≥1000/mm3
  • Platelet count ≥75,000/mm3
• • Calculated creatinine clearance ≥60 ml/min using the Cockcroft-Gault formula below:  See Protocol

• No radiographic or histological evidence of distant metastasis.

• ECOG Performance Status (PS) 0, 1 or 2 (Appendix I).

• Willingness to provide mandatory blood specimens for correlative research (see Section 14.0)

• Willingness to provide mandatory tissue specimens for correlative research (see Section 17.0)

• Willing to return to enrolling institution for follow-up (during the Active Monitoring Phase of the study) 

Exclusion Criteria: 

• Any of the following because this study involves an agent that has known genotoxic, mutagenic, and teratogenic effects:

• • Pregnant persons
  • Nursing persons
  • Persons of childbearing potential and persons able to father a child who are unwilling to employ adequate contraception.
• Co-morbid systemic illnesses or other severe concurrent disease which, in the judgment of the investigator, would make the patient inappropriate for entry into this study or interfere significantly with the proper assessment of safety and toxicity of the prescribed regimens.

• Uncontrolled intercurrent illness including, but not limited to:

• • ongoing or active infection
  • symptomatic congestive heart failure
  • unstable angina pectoris
  • Renal insufficiency (eGFR < 60)
  • or psychiatric illness/social situations that would limit compliance with study requirements.

• Receiving any other investigational agent which would be considered as a treatment for the primary neoplasm.

• Active second malignancy currently receiving systemic treatment ≤6 months prior to pre-registration.

• History of myocardial infarction ≤6 months prior to pre-registration, or congestive heart failure requiring use of ongoing maintenance therapy for life-threatening ventricular arrhythmias.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 12/09/2024. Questions regarding updates should be directed to the study team contact.