The Evaluation of the Relationship Between ADC Values and Gleason Score in the Prostate Cancer

Introduction:The purpose of this study was to evaluate the apparent diffusion coefficient (ADC) values of different grades of prostate cancer (PC) and determine whether the use of ADC values could predict the tumor aggressiveness in PC. Materials and methods: Fourtyseven patients (Gleason score (GS) 6) who underwent prostate multiparametric MRI (1.5 Tesla) between January 2017 and December 2020 for the evaluation of suspicious findings on clinical or laboratory evaluation were enrolled in this study.The specimens which were obtained from systematic 12-core trans-rectal ultrasound (TRUS)-guided biopsy were used for histopathologic diagnoses.The average ADC values within the tumors were calculated.Independent sample t-test, one-way analysis of variance (ANOVA, Tukey's post-hoc or Tamhane) and receiver operating characteristics (ROC) curve analysis were used. Results:The mean ADC value of high-risk patients which was 585.4138.710 - mm 2 /s, was significantly lower than other subgroups (p=0.036).The mean ADC value in low-risk group (798.1236.5 10 -6 mm 2 /s) was significantly higher (p = 0.012) than others.No significant difference in ADC values was found between low-risk vs intermediate-risk groups (p = 0.149) and intermediaterisk vs high-risk groups (p = 0.419).No statistically significant difference in ADC values between GS 3+4 and GS 4+3 (p, 0.552) was found.ROC analysis revealed an optimal ADC cut-off of 59510 -6 mm 2 /s for differentiating high-risk group from the other subgroups (sensitivity, 71%; specificity 67.6%, p, 0.038).For the determination of low-risk group, an ADC cut-off of 66510 -6 mm 2 /s (sensitivity, 80%; specificity, 65.6%, p, 0.017) was found.Discussion: While ADC values may differentiate the high-risk and low-risk tumors, the strength of ADC in the prediction of intermediate-risk tumors was low.The ADC cut-off value of 66510 -6 mm 2 /s showed the high sensitivity and moderate specificity for the detection of low-risk tumors.