Fish Oil Supplement in Rectal Cancer

Neoadjuvant treatment with radiotherapy (RDT) and chemotherapy (CT) are the treatment of choice for rectal adenocarcinomas in stages II and III. This results currently in pathologic complete response in 10% to 30% of cases. The immune and inflammatory response is altered in these individuals and is directly related to response to therapy. Both the disease and the treatment of colorectal cancer have an impact on quality of life and nutritional status. In studies with cells and animal models the incorporation of fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic (DHA) - derived from fish oil - has been shown to interfere in the process of inflammation, cell signaling and gene transcription enhancing the response to treatment. Are reported ability to restore the apoptosis of tumor cells, sensitization of tumor cells to chemotherapy, production of less pro-inflammatory cytokines and the preservation of normal energy and protein metabolism. The aim of this study is to verify if the daily consumption of 2.4 g EPA + DHA for adults in neoadjuvant therapy can promote changes on inflammatory and immunological markers of host response to tumor and if this response is altered by nutritional status. It is expected that supplementation can reflect in control of inflammatory and immune response in favor of tumor cell death contributes to pathological complete response and that it happens with preservation of nutritional status. Subjects will be randomized as to supplementation. All will be assessed in four moments during neoadjuvant therapy and immediate postoperative. Results will be presented by comparing the intervention group and control group at each moment.