To determine the safety and efficacy of in-bore magnetic resonance-guided prostate biopsy (MRGB) for detection of clinically significant disease (CSD) in untreated men with known or suspected prostate cancer (PCa), and to compare MRGB results by Mp-MRI assessment grade.
METHOD AND MATERIALS512 patients underwent multiparametric magnetic resonance imaging (Mp-MRI) followed by MRGB at one of three centers in this IRB-approved, HIPAA-compliant, retrospective study. Exclusion criteria were prior prostate cancer therapy and incomplete Mp-MRI (n = 51). Patients (n = 461) were analyzed in two subcohorts: no prior PCa (NP) (n = 381) and active surveillance (AS) (n = 80). Detection rates of PCa and CSD (Gleason Score at least 3 + 4) were calculated and compared among subcohorts and by Mp-MRI assessment grade (PI-RADS v1 or previously published modified PI-RADS score). Logistic regression was performed to identify predictors for detection of PCa and CSD.
RESULTSMean patient age was 66 years, median prostate-specific antigen (PSA) was 7.5 ng/mL, and median prostate volume was 54 cc. A mean of 1.7 targets was sampled per gland. Significant adverse events (urosepsis and hematuria with obstruction) occurred in 1% (5/461). Overall PCa detection rates were 51% per patient (233/461) and 37% per lesion (282/757). 65% (151/233) of men with detected PCa had CSD. Per patient PCa detection rates in the NP and AS subcohorts were: 47% (178/381) and 69% (55/80), respectively, significantly higher in the AS group (p < 0.001). CSD was detected in 10% (47/451), 43% (96/225) and 84% (68/81) of lesions with Mp-MRI assessment grades of 3, 4 and 5, respectively. Older age, higher PSA, and lower prostate volume predicted MRGB detection of CSD (OR=1.07 and p = 0.003, OR=1.1 and p=0.014, and OR=0.98 and p=0.032, respectively).
CONCLUSIONIn-bore MRGB is safe and high-yield for detection of CSD among men with high and very high suspicion targets (grades 4 and 5). The yield of MRGB for CSD among men with intermediate suspicion targets (grade 3) is lower, such that it may be reasonable to defer biopsy in select cases.
CLINICAL RELEVANCE/APPLICATIONMRGB is a safe and high-yield technique for detecting clinically significant PCa and may be useful in men with suspected PCa but no prior definitive diagnosis and those on AS.