This interventional prospective study aims firstly to investigate variations in lipid levels in blood samples and their potential relationship with the duration and/or intensity of post-operative pain. Secondly, it aims to investigate the activation of peripheral blood mononuclear cells and neutrophils in patient blood samples. The study will enrol women aged 18 years or older who have been newly diagnosed with primary invasive or non-invasive breast cancer requiring surgical removal of the tumour, with or without axillary surgery. The main objectives of the study are To assess whether there is an association between circulating levels of lipid mediators and chronicity (\> 3 months) of postoperative pain after breast cancer surgery. To assess whether circulating levels of lipid mediators can predict chronicity of postoperative pain in breast cancer surgery. To assess the existence of an association between resected tissue levels of lipid mediators and chronicity of postoperative pain in breast cancer surgery. To assess whether tissue levels of lipid mediators can predict chronicity of postoperative pain in breast cancer surgery.