摘要:Despite recent advances in chemotherapy for gastrointestinal cancer, a crucial factor related to poor prognosis is reduced tolerance to chemotherapy induced by cancer cachexia. Fish oil (FO)-derived eicosapentaenoic acid (EPA) modulates inflammation in patients with various malignancies; however, the impact of FO-enriched nutrition as a combined modality therapy on clinical outcomes remains controversial. We systemically analysed chronological changes in biochemical and physiological status using bioelectrical impedance analysis in 128 gastrointestinal cancer patients provided with or without FO-enriched nutrition during chemotherapy. Furthermore, we evaluated the clinical significance of FO-enriched nutrition and clarified appropriate patient groups that receive prognostic benefits from FO-enriched nutrition during treatment of gastrointestinal cancer. The control group showed significant up-regulation of serum CRP) levels and no significant difference in both skeletal muscle mass and lean body mass. In contrast, the FO-enriched nutrition group showed no changes in serum CRP concentration and significantly increased skeletal muscle mass and lean body mass over time. Furthermore, high CRP levels significantly correlated with reduced tolerance to chemotherapy, and FO-enriched nutrition improved chemotherapy tolerance and prognosis, particularly in gastrointestinal cancer patients with a modified Glasgow prognostic score (mGPS) of 1 or 2. We conclude that FO-enriched nutrition may improve the prognosis of patients with cancer cachexia and systemic inflammation (i.e., those with a mGPS of 1 or 2).