 We aimed that to correlate both primary lesion 18F-fluorodeoxyglucose FDG maximum standardized uptake value SUVmax and diffusion-weighted imaging DWI apparent diffusion coefficient ADC with clinicopathological prognostic factors and compare the prognostic value of these indexes in breast cancer in this study. The evaluated and compared parameters are SUVmax and ADC according to age, tumour size, lymph node metastasis, receptor status, histologic grade, modified Nottingham prognostic index. 