Inclusion Criteria:

• Diagnosis of malignant disease of any stage (Stage I through Stage IV).
• No prior history of chemotherapy for any malignancy
• Scheduled to receive intravenous HEC (Highly Emetogenic Chemotherapy) (either cisplatin-containing regimen or doxorubicin and cyclophosphamide [AC]).
  • Cisplatin, given on a single day, at a dose of ≥ 70 mg/m2, with or without other chemotherapy agent(s); or 
  • Doxorubicin (60 mg/m2) plus cyclophosphamide (600 mg/m2).
• No nausea or vomiting ≤ 24 hours prior to registration.
• Negative pregnancy test (serum or urine) done ≤ 7 days prior to registration, for women of childbearing potential only. A female of childbearing potential is a sexually mature female who:
  • has not undergone a hysterectomy or bilateral oophorectomy; or
  • has not been naturally postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in the preceding 12 consecutive months).
• No known diagnosis of dementia. Patients with stable treated brain metastases are eligible to participate.
• No known history of CNS disease (e.g., seizure disorder).
• No treatment with another antipsychotic agent such as olanzapine, risperidone, quetiapine, clozapine, phenothiazine or butyrophenone ≤ 30 days prior to registration.
• No chronic phenothiazine administration as an antipsychotic agent (patients may receive prochloperazine and other phenothiazines as rescue anti-emetic therapy but not within 24 hours prior to registration).
• No use of amifostine within 7 days prior to registration.
• No radiotherapy within 7 days prior to registration or planned for one week after the current dose of chemotherapy.
• No use of quinolone antibiotic therapy within 7 days prior to registration.
• No chronic alcoholism (as determined by the investigator).
• No known hypersensitivity to olanzapine.
• No known uncontrolled cardiac arrhythmia, no known uncontrolled congestive heart failure, or no acute myocardial infarction within the previous six months.
• No history of uncontrolled diabetes mellitus, i.e., no diabetic ketoacidosis; within 6 months prior to registration. Patients are eligible if they have controlled diabetes on diet, oral agents, and/or insulin.
• Age ≥ 18 years old
• ECOG Performance Status 0, 1 or 2.
• Patients must be able to read and comprehend English. Local translation, including verbal translation of PROs is not permitted.
• Required Initial Laboratory Values ≤120 days prior to registration Serum Creatinine ≤ 2.0 mg/dL .
• AST or ALT ≤ 3 x upper limit of normal (ULN).

Exclusion Criteria:

• Any non-compliance with Inclusion Criteria above.