Incidental Large Exophytic Prostatic Cyst in an Asymptomatic Male: Diagnostic Evaluation and Management

Abstract

Prostatic cysts are generally small, intraprostatic, and incidental. Large, multiloculated, exophytic cysts are rare and can mimic pelvic neoplasms. We report an incidental discovery of a large exophytic prostatic cyst in an asymptomatic 57-year-old male. Multiparametric magnetic resonance imaging (mpMRI) demonstrated T1 and T2 hyperintensity, suggesting proteinaceous or hemorrhagic content. Magnetic resonance spectroscopy (MRS) provided essential metabolic context, revealing a preserved citrate peak and a high citrate-to-choline ratio, which supported a benign impression. This was further corroborated by a low prostate-specific antigen (PSA) density (0.068 ng/mL/cc). Transrectal ultrasound–guided aspiration yielded 20 mL of hazy brownish fluid; cytopathology confirmed the absence of malignancy. This case emphasizes the diagnostic value of combining mpMRI, MRS, and PSA density to characterize large, complex prostatic “incidentalomas” non-invasively. Such a multi-modal approach facilitates conservativemanagement, sparing asymptomatic patients from unnecessary surgical intervention even in the

event of subsequent cyst reaccumulation.