Q-GAIN (Using Qpop to Predict Treatment for GAstroIntestinal caNcer)

Inclusion Criteria: \- Patients may be included in the study only if they meet the following criteria: 1. Treatment naïve patient with gastrointestinal cancers (i.e. oesophageal, gastro-oesophgeal, gastric, small bowel, colorectal, hepatocellular, pancreatic and biliary tract) fit and planned for first line treatment, OR 2. Chemo-refractory patients with GI cancers deemed by investigator to be fit for clinical trial 3. Age ≥ 21 years 4. ECOG PS 0-1 5. At least 1 tumour lesion amenable to fresh biopsy 6. At least 1 measurable tumour lesion based on RECIST v 1.1 criteria 7. Estimated life expectancy of at least 24 weeks 8. Adequate organ function , including: 1. Pre-biopsy o Bone marrow: * Absolute neutrophil (segmented and bands) count (ANC) ≥1.5 x 109/L * Platelets ≥ 100 x 109/L * Pro-Thrombin within ULN * Hemoglobin ≥ 8 x 109/L 2. Pre-treatment * Bone marrow: * Absolute neutrophil (segmented and bands) count (ANC) ≥1.5 x 109/L * Platelets ≥ 100 x 109/L * Hemoglobin ≥ 8 x 109/L * Hepatic: * Bilirubin ≤ 1.5 x upper limit of normal (ULN), * ALT or AST ≤ 2.5x ULN, (or ≤ 5 X with liver metastases) * Renal: * Creatinine ≤ 1.5x ULN 9. Signed informed consent from patient or legal representative 10. Able to comply with study-related procedures. 11. Recovery from prior toxicity to G1, excluding alopecia. Exclusion Criteria: * There are no specific exclusion criteria if patients meet the inclusion criteria