The omega-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are normal constituents of the diet and are essential in maintaining important cellular functions. They have been shown to have anticancer activity, both in vitro and in human tumor xenografts. Clinical studies have shown that patients with different types of cancer may have beneficial effects of omega-3 PUFAs alone or in combination with chemo- and radiotherapy, suggesting omega-3 PUFAs as potent adjuvants to traditional cancer therapy. Different mechanisms behind the anti-cancer effects of omega-3 PUFAs have been proposed, but much is still unknown. In-depth understanding of intra- and inter-tumor heterogeneity and the interactions with tumor microenvironments influenced by genomic variation, dietary, lifestyle and environmental factors, is essential in order to improve personalized diagnostics and treatment. By combining basal and clinical research, our research is highly relevant for translational medicine. Although nutrigenomics is a science still in its infancy, there is tremendous potential for the application of nutrition in cancer prevention and management. https://www.ntnu.edu/ikom/crc/genelipid#/view/about