Eicosanoids are derivatives of three different PUFA, vital in membrane formation and anti-inflammatory control. The presence of eicosanoids in adipose tissue and fibroblasts governs the release of signalling agents in breast, stimulating the invasion of breast cancer cells. Lipid composition has emerged as a potential predictor of breast cancer. However, current research focuses on the tumour initiation, while the understanding of lipid function in tumour progression remains sparse. We therefore hypothesise that there is a difference in PUFA concentration between grade II and III breast cancer. We applied MQC MRS for accurate PUFA measurement on freshly excised whole breast tumours.