Utility of multiparametric mri adc values in assessment of prostate cancer gleason score.

Objectives. One of the leading cancers in male population remains prostate cancer (PCa). Multiparametric
magnetic resonance imaging (mp-MRI) has gradually taken on a large role in diagnosis of PCa. Studies on
apparent diffusion coefficient (ADC) have shown improved accuracy in detection of clinically significant
PCa (csPCa). The aim of this study was to evaluate if ADC values could be used to predict Gleason score
(GS).
Materials and Methods. A retrospective analysis on 365 patients aged 47-79 years (from January 2019
to December 2022) who underwent a previous mp-MRI (1.5T) with PI-RADS v2.1 ≥ 3/5 and a following
histopathology diagnosis of GS ≥ 6 according to results of radical prostatectomy (RP). All suspected lesions
were evaluated by certified radiologists and DWI ADC values in 10⁻3 mm2
/s were measured using b values
50 and 1000.
Results. Histopathology revealed clinically significant PCa in 278 patients (GS ≥ 7) and non-significant
PCa (nsPCa) in 87 patients (GS ≤ 6). Data analysis demonstrated a characteristic distribution of value
based on GS 6-10 (ADCmean ≥ 0.867×10-3 mm2
/s for GS 6; ADCmean ranging from 0.621×10-3 to
0.708×10-3 mm2
/s for GS 7; ADCmean ≤ 0.558×10-3 mm2
/s for GS 8,9,10), with a very strong statistically
significant negative correlation (rs
= –0.832; P < 0.0001). However, overlapping values in GS 6-7 groups
in 4.8% cases were noted. ROC analysis displayed a significant correlation at ADC threshold value of
0.790×10-3 mm2
/s (P < 0.0001, AUC = 0.980), with sensitivity 95%, specificity 91.7%, PPV 95%, NPV
90% and overall accuracy of 94%.
Conclusions. DC analysis shows prominent capability in defining tumor aggressiveness in clinically
significant cancers (GS ≥ 7), which could assist as a dependable biomarker to grade suspected lesions and
select patients for targeted biopsy. However, more studies are necessary as there is limitation of measurements
in GS 6-7 g roups