Malacoplakia in a 49-year-old man with recurrent episodes of acute prostatitis 6 months earlier and elevated PSA level. Transrectal US–guided biopsy showed malacoplakia. (a) High-power photomicrograph shows inflammatory infiltrate with pathognomonic intracellular Michaelis-Gutmann inclusion bodies (arrow). (Original magnification, ×600; H-E stain.) (b–d) Axial T2-weighted image (b), axial ADC map (c), and axial ktrans image (d) show diffuse peripheral zone abnormality (arrows) with low T2 signal intensity, low ADC, and enhancement.