GI-05: The Impact of Olanzapine Among Patients Receiving Neoadjuvant Chemotherapy for Gastric Cancer

Inclusion Criteria:

* Age ≥ 18 years of age at time of consent
* Eastern Cooperative Oncology Group (ECOG) score of 0-2
* Histologically confirmed gastric adenocarcinoma, documented by biopsy.
* Planned to receive neoadjuvant chemotherapy followed by surgical resection, as determined by the treating oncologist.
* Demonstrates adequate organ function. All screening labs are to be obtained within 30 days prior to registration.
* Able to provide written informed consent and HIPAA authorization for release of personal health information, via an approved UIC Institutional Review Board informed consent form and HIPAA authorization. If a subject is unable to consent, a Legally Authorized Representative (LAR) may provide consent on their behalf.
* Women of childbearing potential must not be pregnant or breastfeeding. A negative serum or urine pregnancy test is required per institutional practice guidelines.
* As determined at the discretion of the enrolling physician or protocol designee, the ability of the subject to understand and comply with study procedures for the entire length of the study

Exclusion Criteria:

* Active infection requiring systemic therapy
* Uncontrolled HIV/AIDS or active viral hepatitis
* Pregnant or nursing
* Any prior or concurrent malignancy whose natural history or treatment has the potential to interfere with the safety or efficacy assessment of this investigational regimen, as determined by the treating medical oncologist.
* Patients with a feeding tube (e.g., gastrostomy or jejunostomy) who receive their primary source of nutritional intake via enteral tube feeding at the time of enrollment are excluded because the primary endpoints of appetite and weight change may not accurately reflect oral intake or appetite response in this population.
* Other major comorbidity, as determined by the study PI
* Patients currently taking medications that may interact with olanzapine, including, but not limited to, other anti-psychotics, CNS depressants, or dopamine agonists.
* Patients with a clinically significant cardiac history or clinically significant QTc prolongation that, in the opinion of the treating investigator, would make olanzapine administration unsafe.
* Patients with uncontrolled hyperglycemia that, in the opinion of the treating investigator, would make olanzapine administration unsafe.