Fish Oil Supplementation in Gastrointestinal Cancer

This study will be divided into three stages defined as: baseline (T0), middle moment (T1) and final moment (T2). At baseline, will be performer the patients identification, clinical data collection, assessment of anthropometric data and body composition, blood sample collection and questionnaires application for individuals allocated into two groups (Fish Oil Group and Placebo Group). The Fish Oil Group (GOP) will receive fish oil capsules and the placebo group (GP) will receive capsules containing olive oil, both also will receive consumption guidelines. The list of randomization was generated by a computer program and was divided by cancer localization and gender. The researchers involved with the recruitment had access only to randomization list containing codes. The codes were distributed sequentially. The baseline is the day of first chemotherapy. In the middle moment, five weeks after the start of study, new blood collection, questionnaires and measurement of anthropometric data will be performed. At the final moment, nine weeks after baseline, last blood collection, questionnaires and measurement of anthropometric data and body composition of fish oil and placebo groups will be performed, and will feature the end of the capsules consumption. After 6 months and 1 year after the initiation of chemotherapy and supplementation with fish oil or placebo, survival data will be collected. Throughout the monitoring period, the researcher and collaborators will maintain contact with the individuals included. The contact will be made in CEPON, where they receive chemotherapy, and by telephone.