The investigators are developing a novel standardized and centralized approach named Integrated Personalized Functional Profiling (PFP) in Luxembourg. Based on recent improvements in cancer biopsy-derived 3D-culture technologies the PFP process will screen patient derived cells (PDCs) with FDA/EMA-approved drugs to generate personalized functional response profiles. The selected drug through PFP technology will provide personalized treatment recommendation for the patient.

This pilot study will evaluate the clinical feasibility of setting-up an effective workflow as a first step. Outcomes from this study will be used subsequently to help plan the clinical validation of the implementation of PFP.

Inclusion Criteria:

• Patient with recurrent Glioblastoma (rGBM) or with metastatic gastrointestinal cancer (mGIC), i.e. adenocarcinoma (any grade) of stomach, liver, pancreas, small intestine, colon, rectum
• The patient has received previous cancer treatment for mGIC or rGBM
• Male or female ≥ 18 years
• Life expectancy ≥ 12 weeks
• Histologically or cytologically confirmed diagnosis for mGIC or recurrence of a glioblastoma, WHO grade IV
• For women of childbearing potential, a negative pregnancy test documented prior to the screening visit is required
• Signed Inform Consent Form before any study related procedure

Exclusion Criteria:

• For female patient, being pregnant, planning a pregnancy or breastfeeding
• No fresh and viable tumor material available
• Known active Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), or Hepatitis C Virus (HCV) infection
• Uncontrolled medical conditions (i.e, diabetes mellitus, hypertension, etc), psychological, familial, sociological, or geographical conditions that do not allow compliance with the protocol; or unwillingness or inability to follow the procedures required in the protocol
• In mGIC arm, patient with non-adenocarcinoma gastrointestinal cancer
• Patient unable to understand and consent himself