Immunonutrition and Quality of Life of Cancer Patients Undergoing Oncological Treatment

Inclusion Criteria: * Histologically proven GI cancer. * Age ≥ 18 years. * Life expectancy more than 3 months. * Female patients of child-bearing potential must be willing to employ effective contraception during the study period. * Female patients of child-bearing potential must have a negative serum Beta Human Chorionic Gonadotrophin (βhCG) test at Visit 0. * The patient is able to communicate effectively with study personnel and is considered reliable, willing, and cooperative in terms of compliance with the protocol requirements. * The patient voluntarily gives written informed consent to participate in the study. Exclusion Criteria: * Severe concomitant clinical conditions other than the previously untreated digestive tract cancer that jeopardise the protocol follow-up. * The patient is pregnant or is a lactating woman. * Currently participating or having participated in another interventional clinical trial related to nutritional support during the 30 days prior to the beginning of the study product intake, except if this other interventional trial is testing new drug or surgical intervention. (Note: participation in a prior or concurrent clinical trial not related to nutritional support does not exclude the patient from participation.) * Other malignancies in the last 5 years (except for successfully treated in situ basocellular skin and in situ cervical uterine tumours). * Patients with more than 20% weight loss over a 6 months period.