Diagnostic Performance of Multiparametric MR Imaging According to the Location of Prostate Cancer

Background/Objectives: Most prostate cancers occur in the peripheral zone (PZ) of prostate and a few in the transition zone (TZ). We compared MRI findings and clinicobiologic findings among PZ, TZ and PZ+TZ prostate cancers to determine if cancer location is independently associated with outcomes.

Methods/Statistical Analysis: A retrospective study was performed of 70 men who underwent multiparametric-MRI prior to radical prostatectomy from 2014.03~2018.02. Fifty-two prostate cancers were included in this study. We investigated the comparison serum-PSA, tumor size, prostate weight, Gleason score, presence of extracapsular extension, ADC value on DWI, PIRADS category and pathologic tumor stage, according to the location of prostate cancer (PZ, TZ, and PZ+TZ prostate cancers), using statistical methods.

Findings: 30/52(58%) were PZ in location, 14/52(27%) were in TZ, and 8/52(15%) were with PZ+TZ prostate cancer. Patients with PZ+TZ cancer presented with large total cancer size (≤ 1.5cm), MRI evidence of presence of extracapsular invasion (p < 0.001), seminal vesicle invasion (p = 0.026) and lymph node invasion (p < 0.001). The mean ADC value was significantly lower in the PZ+TZ cancer (mean ADC 0.455 – 0.83 (median 0.643)) than in PZ (0.4555 – 1.342 (median 0.90)) and TZ cancer (0.579 – 1.211 (median 0.895)) (p=0.005). There was no significant difference related to serum PSA (p value 0.065), Gleason score (p value 0.235) between PZ, TZ and PZ+TZ lesion.

Improvements/Applications: PZ+TZ prostate cancer is associated with tumor, ECE, seminal vesicle invasion and low ADC value. So, tumor location should be taken into account in the process of evaluation, and mp-MRI can be a good tool to staging prostate cancer.