This study is a single arm, non-randomized feasibility study with tolerability and toxicity evaluation as primary endpoints which seeks to determine if a modified administration schedule of capecitabine with oxaliplatin will result in less toxicity than standard FOLFOX or CAPOX regimens.

Inclusion Criteria:

• Patient with GI malignancy
• Provider plans non-curative intent treatment with either CAPOX or FOLFOX (mFOLFOX6) at standard dosages for >3 months NOTE: Patient is not required to have radiologically measurable disease. NOTE: Planned administration of other anti-cancer medications (eg bevacizumab, epidermal growth factor receptor antibodies, immunotherapy, tyrosine kinase inhibitors) is allowed.

Exclusion Criteria:

• Patients not meeting standard hematologic parameters for chemotherapy administration as follows:

  • Absolute neutrophil count (ANC) ≥ 1500
  • Platelet count ≥ 100,000 Patients not meeting standard liver function parameters for chemotherapy administration as follows:
  • AST ≤ 5x ULN
  • ALT ≤ 5X ULN
  • Total Bilirubin ≤ 1.5X ULN Patients not meeting standard renal function parameters for chemotherapy administration as follows:
  • Serum Creatinine ≤ 1.2 or creatinine clearance ≥ 30 ml/min NOTE: Planned administration of another cytotoxic chemotherapy (eg irinotecan) is an exclusion.

Anonymized patient related data will be incorporated into publications and will be made available to other investigators at reasonable request.