Figure 9b. Biopsy-proved adenocarcinoma in a 65-year-old man with a previous negative biopsy result and a continuously elevated prostate-specific antigen level. (a) Axial T2-weighted MR image shows no focal lesion in the prostate. (b, c) MR spectroscopic image (b) and corresponding spectrum (c) demonstrate an elevated ratio (in arbitrary units) of choline (Ch) and creatine (Cr) to citrate (Ci) in the central gland (arrow in b), a finding indicative of prostate cancer, which was confirmed at targeted biopsy.