Inclusion Criteria:  Patients must be ≥ 75 years old Performance status 0, 1 or 2 Diagnostic of digestive cancer, all stages (adjuvant or metastatic), with an indication for chemotherapy treatment or targeted therapy Patients previously treated with one or several lines of chemotherapy for this digestive cancer are eligible Estimated life expectancy ≥ 3 months Patients able to speak, read and understand French Signed informed consent from the patient Patients must have a social security coverage  Exclusion Criteria:  History of differentiated neuroendocrine tumors grade 1 or 2 (pancreas, small intestine) History of another treated cancer during the last five years History of major surgery and/or curative radiation therapy during the last 4 weeks before inclusion Patients unable to submit to medical follow-up for geographical, social or psychological reasons Patients placed under guardianship