Jamie N Holtz1, Rachel Kloss Silverman2, Kae Jack Tay3,4, Jill T Browning5, Jiaoti Huang5, Thomas J Polascik3,4, Rajan T Gupta6,7,8. 1. Department of Radiology, Duke University Medical Center, DUMC Box 3808, Durham, NC, 27710, USA. 2. Department of Biostatistics, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, 3101 McGavran-Greenberg Hall, CB #7420, Chapel Hill, NC, 27599, USA. 3. Duke Cancer Institute, DUMC Box 3917, Durham, NC, 27710, USA. 4. Department of Surgery, Division of Urologic Surgery and Duke Prostate Center, Duke University Medical Center, DUMC Box 2804, Durham, NC, 27710, USA. 5. Department of Pathology, Duke University Medical Center, DUMC Box 3712, Durham, NC, 27710, USA. 6. Department of Radiology, Duke University Medical Center, DUMC Box 3808, Durham, NC, 27710, USA. rajan.gupta@duke.edu. 7. Duke Cancer Institute, DUMC Box 3917, Durham, NC, 27710, USA. rajan.gupta@duke.edu. 8. Department of Surgery, Division of Urologic Surgery and Duke Prostate Center, Duke University Medical Center, DUMC Box 2804, Durham, NC, 27710, USA. rajan.gupta@duke.edu.
Abstract
PURPOSE: Our objective is to determine the accuracy of multiparametric MRI (mpMRI) in predicting pathologic grade of prostate cancer (PCa) after radical prostatectomy (RP) using simple apparent diffusion coefficient metrics and, specifically, whether mpMRI can accurately separate disease into one of two risk categories (low vs. higher grade) or one of three risk categories (low, intermediate, or high grade) corresponding to the new prognostic grade group (PGG) criteria. METHODS: This retrospective, HIPAA-compliant, IRB-approved study included 140 patients with PCa who underwent 3 T mpMRI with endorectal coil and transrectal ultrasound-guided (TRUS-G) biopsy before RP. MpMRI was used to classify lesions using a two-tier (low-grade/PGG 1 vs. high-grade/PGG 2-5) or a three-tier system (low-grade/PGG 1 vs. intermediate-grade/PGG 2 vs. high-grade/PGG 3-5). Accuracy of mpMRI was compared against RP for each system. RESULTS: The predictive accuracy of mpMRI using the two-tier system is higher than when using three-tier system (0.77 and 0.45, respectively). There were similar rates of undergrading between mpMRI and TRUS-G biopsy compared to RP (16% & 21%; respectively); rate of overgrading was higher for mpMRI vs. TRUS-G biopsy compared to RP (42% & 17%, respectively). When mpMRI and TRUS-G biopsy are combined, rate of undergrading is 1.4% and overgrading is 11%. CONCLUSIONS: MpMRI predictive accuracy is higher when using a two-tier vs. a three-tier system, suggesting that advanced metrics may be necessary to delineate intermediate- from high-grade disease. Rates of under- and overgrading decreased when mpMRI and TRUS-G biopsy are combined, suggesting that these techniques may be complementary in predicting tumor grade.
PURPOSE: Our objective is to determine the accuracy of multiparametric MRI (mpMRI) in predicting pathologic grade of prostate cancer (PCa) after radical prostatectomy (RP) using simple apparent diffusion coefficient metrics and, specifically, whether mpMRI can accurately separate disease into one of two risk categories (low vs. higher grade) or one of three risk categories (low, intermediate, or high grade) corresponding to the new prognostic grade group (PGG) criteria. METHODS: This retrospective, HIPAA-compliant, IRB-approved study included 140 patients with PCa who underwent 3 T mpMRI with endorectal coil and transrectal ultrasound-guided (TRUS-G) biopsy before RP. MpMRI was used to classify lesions using a two-tier (low-grade/PGG 1 vs. high-grade/PGG 2-5) or a three-tier system (low-grade/PGG 1 vs. intermediate-grade/PGG 2 vs. high-grade/PGG 3-5). Accuracy of mpMRI was compared against RP for each system. RESULTS: The predictive accuracy of mpMRI using the two-tier system is higher than when using three-tier system (0.77 and 0.45, respectively). There were similar rates of undergrading between mpMRI and TRUS-G biopsy compared to RP (16% & 21%; respectively); rate of overgrading was higher for mpMRI vs. TRUS-G biopsy compared to RP (42% & 17%, respectively). When mpMRI and TRUS-G biopsy are combined, rate of undergrading is 1.4% and overgrading is 11%. CONCLUSIONS: MpMRI predictive accuracy is higher when using a two-tier vs. a three-tier system, suggesting that advanced metrics may be necessary to delineate intermediate- from high-grade disease. Rates of under- and overgrading decreased when mpMRI and TRUS-G biopsy are combined, suggesting that these techniques may be complementary in predicting tumor grade.
Entities:
Keywords:
Multiparametric prostate MRI; Prognostic grade groups; Prostate cancer