The detection of prostate cancer (CaP) has increasingly being carried out by multiparametric magnetic resonance imaging (mpMRI). Despite many previous studies, the sensitivity for clinically significant CaP (csCaP) was high, information on mpMRI false-negative lesions is limited. Therefore, the aim of this study was to evaluate the use and limitations of mpMRI in CaP.
A total of 228 CaP foci in 100 patients who underwent 1.5 T mpMRI and radical prostatectomy between December 2015 and June 2017 were retrospectively analyzed. The sensitivities of CaP foci, csCaP, and index tumors (ITs) were measured. Clinically significant CaP was defined into two categories based on the Gleason score (GS): csCaP/GS ≥ 3 + 4 (GS ≥ 3 + 4 or diameter > 10 mm) and csCaP/GS ≥ 4 + 3 (GS ≥ 4 + 3 or diameter > 10 mm). In addition, the characteristics of false-negative lesions were identified. The Prostate Imaging Reporting and Data System version 2 was used to determine an mpMRI positive lesion, defined as a lesion having a score of ≥ 3.
The sensitivity of all legions, csCaP/GS ≥ 3 + 4, csCaP/GS ≥ 4 + 3, and ITs were 61.4%, 75.8%, 83.0%, and 91%, respectively. There were 91 lesions that were mpMRI false, 40% of which were csCaP/GS ≥ 3 + 4. There were three lesions with a GS of ≥ 8 and ≥ 10 mm in the false-negative results.
mpMRI can highly detect ITs and csCaP/GS ≥ 4 + 3; however, a few large and high-GS CaPs constitute undetectable lesions in 1.5 T mpMRI.