We demonstrate correlations between hyperpolarised [1-13C]lactate labelling, percentage of Gleason pattern 4 (%GP4) disease, proton (1H) MRI-derived apparent diffusion coefficient (ADC) as a measure of cellularity, the number of tumour epithelial cells measured on histology, combined epithelial LDH expression, and the epithelium-to-stroma MCT4 ratio. The gene discussed is SLC16A3; the disease is neoplasm.