Prostate cancer is the most frequently diagnosed malignancy in the western male population and the associated socio-economic impact on healthcare is more than worrying. There is one key feature of confined (stage T2) prostate cancer that needs to be addressed with immediate urgency: its true aggressiveness. Not all cancers are life threatening and early diagnosis, although needed to improve outcome, will lead to overtreatment of patients with indolent prostate cancer resulting in unnecessary treatment-related morbidity. Therefore, methods to identify clinically significant forms of prostate cancer have to be developed. To pursue this, the initial assessment of the extent of the disease process (clinical staging) needs to be adequate. Obtaining pre-treatment representative tumor tissue (biopsies) is a major clinical challenge, as the disease is often multi-focal and heterogeneous. Accurate functional in vivo imaging modalities could guide these biopsies. Modern genomics technologies have identified numerous cancer cell-associated genetic markers being expressed in prostate cancer tissue or body fluids. Closing the gap between genomics and a non-invasive metabolic assessment of the in vivo prostate, we propose to identify new in vivo targets/biomarkers indicating confined prostate cancer aggressiveness with the underlying central hypothesis: early functional metabolic differences in different tumor foci determine whether it will grow into life-threatening prostate cancer or not. To track these early metabolic differences, the very latest magnetic resonance methodologies, including 13C MR of hyperpolarized metabolites and 1H- and 31P-MRSI of the in vivo human prostate at a field strength of 7 Tesla, will be further developed and implemented. In the well-established translational research environment at the host institution, potential new biomarkers translate into molecular diagnostics or imaging tools for an accurate individual assessment of cancer aggressiveness.