THE ROLE OF THE APPARENT DIFFUSION COEFFICIENT OF THE BIPARAMETRIC MRI AS AN IMAGING MARKER OF PROSTATE CANCER

Probl Radiac Med Radiobiol. 2021 Dec:26:541-553. doi: 10.33145/2304-8336-2021-26-541-553.
[Article in English, Ukrainian]

Abstract

Prostate cancer (PCa) is the most common malignancy in men. The role of the apparent diffusion coefficient (ADC)of biparametric MRI (biMRI) which is a study without the use of dynamic contrast enhancement (DCE), in detectionof PCa is still not comprehensively investigated.

Objective: The goal of the study was to assess the role of ADC of biMRI as an imaging marker of clinically significant PCaMaterials and methods. The study involved 78 men suspected of having PCa. All patients underwent a comprehensive clinical examination, which included multiparametric MRI of the prostate, a component of which was biMRI. TheMRI data was evaluated according to the PIRADS system version 2.1.

Results: The distribution of patients according to the PIRADS system was as follows: 1 point - 9 (11.54 %)patients, 2 points - 12 (15.38 %) patients, 3 points - 25 (32.05 %) patients, 4 points - 19 (24.36 %) patients and5 points - 13 (16.67 %) patients. In a subgroup of patients with 5 points, clinically significant PCa was detected in 100 % of cases. In the subgroup of patients with tumors of 4 points clinically significant PCa was diagnosed in 16of 19 (84.21 %) cases, and in 3 (15.79 %) patients - clinically insignificant tumor. In the subgroup of patients with3 points, clinically significant PCa was diagnosed in 11 of 25 (44.0 %) cases, in 8 (32.0 %) patients - clinicallyinsignificant tumor and in 6 (24.0 %) patients - benign prostatic hyperplasia. PCa with a score of 7 on the Gleasonscale showed significantly lower mean values of ADC of the diffusion weighted MRI images compared to tumors witha score of < 7 on the Gleason scale: (0.86 ± 0.07) x 103 mm2/s vs (1.08 ± 0.04) x 103 mm2/s (р < 0.05).

Conclusions: The obtained results testify to the high informativeness of biMRI in the diagnosis of prostate cancer.The use of ADC allowed to differentiate clinically significant and insignificant variants of the tumor, as well asbenign changes in prostate tissues and can be considered as a potential imaging marker of PCa.

Rak peredmikhurovoï zalozy (RPZ) ie naĭbil'sh poshyrenoiu zloiakisnoiu pukhlynoiu sered cholovikiv. Rol' vymiriuvanogo koefitsiienta dyfuziï (VKD) biparametrychnoï MRT (biMRT) – doslidzhennia bez vykorystannia dynamichnogo kontrastnogo posylennia (DKP) pry vyiavlenni RPZ vse shche zalyshaiet'sia do kintsia ne vyvchenoiuMeta. Metoiu roboty bulo vyvchyty rol' VKD biMRT iak promenevogo markera klinichno znachushchogo RPZ. Materialy ta metody. U doslidzhenni vzialy uchast' 78 cholovikiv z pidozroiu na naiavnist' RPZ. Usim patsiientambulo provedeno kompleksne klinichne obstezhennia, iake vkliuchalo mul'typarametrychnu MRT peredmikhurovoïzalozy, komponentom iakoï bula biMRT. Otsinka danykh MRT bula provedena vidpovidno do systemy PIRADSversiï 2.1. Rezul'taty. Rozpodil patsiientiv zgidno z systemoiu PIRADS buv takym: 1 bal – 9 (11,54 %) patsiientiv, 2 baly –12 (15,38 %), 3 baly – 25 (32,05 %), 4 baly – 19 (24,36 %) ta 5 baliv – 13 (16,67 %) osib. U pidgrupi patsiientivz 5 balamy klinichno znachushchyĭ RPZ buv vyiavlenyĭ u 100 % vypadkiv. U pidgrupi patsiientiv z pukhlynamy v 4 baly klinichno znachushchyĭ RPZ diagnostuvaly u 16 z 19 (84,21 %) vypadkiv, a u 3 (15,79 %) patsiientiv – klinichno neznachushchu pukhlynu. U pidgrupi patsiientiv iz 3 balamy klinichno znachushchyĭ RPZ diagnostovano u 11 z 25 (44,0 %) vypadkiv, u 8 (32,0 %) patsiientiv – klinichno neznachushchu pukhlynu ta u 6 (24,0 %) patsiientiv – dobroiakisnu giperplaziiu peredmikhurovoï zalozy. RPZ z otsinkoiu > 7 za shkaloiu Glisona prodemonstruvaly znachno nyzhchi seredniznachennia VKD dyfuziĭno zvazhenykh zobrazhen' MRT u porivnianni z pukhlynamy z otsinkoiu < 7 za shkaloiu Glisona: (0,86 ± 0,07) x 10 3 mm2/s proty (1,08 ± 0,04) x 10 3 mm2/s (r < 0,05). Vysnovky. Otrymani rezul'taty svidchat' pro vysoku informatyvnist' biMRT v diagnostytsi raku peredmikhuro¬voï zalozy. Zastosuvannia VKD dozvolylo dyferentsiiuvaty klinichno znachushchyĭ i neznachushchyĭ varianty pukhlynnogo protsesu, a takozh dobroiakisni zminy v tkanynakh peredmikhurovoï zalozy i mozhe rozgliadatys' u iakosti potentsiĭnogo promenevogo markeru RPZ.

Keywords: PIRADS; apparent diffusion coefficient; biparametric MRI; diagnosis; marker; prostate cancer.

MeSH terms

  • Aged
  • Biomarkers, Tumor / standards*
  • Diffusion Magnetic Resonance Imaging / methods*
  • Diffusion Magnetic Resonance Imaging / standards*
  • Humans
  • Male
  • Middle Aged
  • Practice Guidelines as Topic*
  • Prostate / diagnostic imaging*
  • Prostatic Neoplasms / diagnosis*
  • Prostatic Neoplasms / epidemiology
  • Prostatic Neoplasms / physiopathology*
  • Sensitivity and Specificity
  • Ukraine / epidemiology

Substances

  • Biomarkers, Tumor