Changes Observed in Multiparametric Prostate Magnetic Resonance Imaging Characteristics Correlate With Histopathological Development of Chronic Granulomatous Prostatitis After Intravesical Bacillus Calmette-Guerin Therapy

Abstract

Administration of Bacillus Calmette-Guerin (BCG) has been shown to cause granulomatous prostatitis, a rare inflammatory process that can be mistaken for prostate cancer (PCa). We present a case of a 78-year-old male on active surveillance (AS) for PCa with a subsequent diagnosis of high-grade urothelial carcinoma. Following intravesical BCG therapy, he developed chronic granulomatous prostatitis (CGP). We present serial MRI and biopsy data demonstrating the time interval between BCG administration and the manifestation of CGP.

Granulomatous Prostatitis after Bacille Calmette-Guérin Instillation Resembles Prostate Carcinoma: A Case Report

“…With the inability to differentiate between granulomatous prostatitis and prostate cancer on transrectal ultrasound [23], speci c characteristics of BCG-induced granulomatous prostatitis on MP-MRI have been proposed recently. In the case patient, an abnormal focus showed low signal in T2-weighted images and an apparent diffusion coe cient in the peripheral zone, which has been reported previously [22,24,25,29,37]. These characteristics could occur because the histology of granulomatous prostatitis includes stromal in ltration of chronic in ammatory cells and extracellular uid surrounding the prostatic cells.…”

“…It seems that prostate biopsy should be delayed in these patients while PSA is monitored. However, two patients whose PSA level was elevated after BCG instillations were pathologically diagnosed with both granulomatous prostatitis and prostate cancer [24,25]. In an epidemiological study, concomitant prostate cancer was reported in 35.9% of patients with granulomatous prostatitis [17].…”

“…BCG instillation was stopped, and the patient received antituberculosis treatment after histopathological diagnosis with BCG-induced granulomatous prostatitis. Most BCG-induced granulomatous prostatitis is asymptomatic and does not require treatment [24,29]. The 4-quinolones and antituberculotics including isoniazid, rifapentine, pyrazinamide, and ethambutol are used in symptomatic BCG-induced granulomatous prostatitis and some BCG-induced prostatic abscesses [23,28,[50][51][52].…”

“…Several cases have reported that granulomatous prostatitis presents as increased serum levels of prostate-speci c antigen (PSA) and a node with an abnormal signal detected by multiparametric prostate magnetic resonance imaging (MP-MRI). Furthermore, previous cases involved nodular or diffusely rm enlargement on digital rectal examination, which was suggestive of prostate cancer and only resulted in a diagnosis of granulomatous prostatitis after prostate biopsy [22][23][24][25]. Here, we present a case of granulomatous prostatitis induced by BCG instillation and describe how to differentiate between granulomatous prostatitis induced by BCG instillation and prostate cancer.…”

Granulomatous prostatitis after bacille Calmette-Guérin instillation resembles prostate carcinoma: A case report and review of the literature

“…It seems that prostate biopsy should be delayed in these patients while PSA is monitored. However, two patients whose PSA level was elevated after BCG instillations were pathologically diagnosed with both granulomatous prostatitis and prostate cancer [ 26 , 27 ]. In an epidemiological study, concomitant prostate cancer was reported in 35.9% of patients with granulomatous prostatitis[ 17 ].…”