False-positive mpMRI and true-negative

Background: Xanthogranulomatous prostatitis (XGP) is a rare disorder of the prostate. It presents as a hard fixed nodule on digital rectal examination (DRE), and may cause obstructive urinary symptoms and elevated serum prostate-specific antigen (PSA) levels, therefore mimicking prostate cancer (PCa) clinically and biochemically. Radiological features of XGP overlap with those of PCa, and the 2 conditions cannot be distinguished by pelvic multiparametric magnetic resonance imaging (mpMRI). Case Description: We report the case of a 56-year-old man who had slowly progressing dysuria for 10 years, which was significantly worse for 1 week, and a PSA level of 49.19 ng/L. Ultrasound revealed a hypoechoic lesion in the left periphery of the prostate, which was hypointense with capsular irregularity on axial T2-weighted imaging (T2WI), hyperintense on the diffusion weighted imaging (DWI), and hypointense on the apparent diffusion coefficient (ADC) maps resulting in a Prostate Imaging-Reporting and Data System (PI-RADS) score of 5. The patient was highly suspected of having high-risk PCa and underwent a Conclusions: Non-uptake of PSMA in a lesion may still provide information for a diagnosis by exclusion or regular follow-up checks in patients that are highly suspected to have PCa in clinic or on mpMRI.