Athina C Tsili1, Alexandra Ntorkou2, Loukas Astrakas3, Vasilis Xydis4, Stavros Tsampalas5, Nikolaos Sofikitis6, Maria I Argyropoulou7. 1. Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: a_tsili@yahoo.gr. 2. Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: alexdorkou@hotmail.com. 3. Department of Medical Physics, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: astrakas@uoi.gr. 4. Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: vxydis@cc.uoi.gr. 5. Department of Urology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: stamp@gmail.com. 6. Department of Urology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: akrosnin@hotmail.com. 7. Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina, Greece. Electronic address: margyrop@cc.uoi.gr.
Abstract
INTRODUCTION: To evaluate the difference in apparent diffusion coefficient (ADC) measurements at diffusion-weighted (DW) magnetic resonance imaging of differently shaped regions-of-interest (ROIs) in testicular germ cell neoplasms (TGCNS), the diagnostic ability of differently shaped ROIs in differentiating seminomas from nonseminomatous germ cell neoplasms (NSGCNs) and the interobserver variability. MATERIALS AND METHODS: Thirty-three TGCNs were retrospectively evaluated. Patients underwent MR examinations, including DWI on a 1.5-T MR system. Two observers measured mean tumor ADCs using four distinct ROI methods: round, square, freehand and multiple small, round ROIs. The interclass correlation coefficient was analyzed to assess interobserver variability. Statistical analysis was used to compare mean ADC measurements among observers, methods and histologic types. RESULTS: All ROI methods showed excellent interobserver agreement, with excellent correlation (P<0.001). Multiple, small ROIs provided the lower mean ADC in TGCNs. Seminomas had lower mean ADC compared to NSGCNs for each ROI method (P<0.001). Round ROI proved the most accurate method in characterizing TGCNS. CONCLUSION: Interobserver variability in ADC measurement is excellent, irrespective of the ROI shape. Multiple, small round ROIs and round ROI proved the more accurate methods for ADC measurement in the characterization of TGCNs and in the differentiation between seminomas and NSGCNs, respectively.
INTRODUCTION: To evaluate the difference in apparent diffusion coefficient (ADC) measurements at diffusion-weighted (DW) magnetic resonance imaging of differently shaped regions-of-interest (ROIs) in testicular germ cell neoplasms (TGCNS), the diagnostic ability of differently shaped ROIs in differentiating seminomas from nonseminomatous germ cell neoplasms (NSGCNs) and the interobserver variability. MATERIALS AND METHODS: Thirty-three TGCNs were retrospectively evaluated. Patients underwent MR examinations, including DWI on a 1.5-T MR system. Two observers measured mean tumor ADCs using four distinct ROI methods: round, square, freehand and multiple small, round ROIs. The interclass correlation coefficient was analyzed to assess interobserver variability. Statistical analysis was used to compare mean ADC measurements among observers, methods and histologic types. RESULTS: All ROI methods showed excellent interobserver agreement, with excellent correlation (P<0.001). Multiple, small ROIs provided the lower mean ADC in TGCNs. Seminomas had lower mean ADC compared to NSGCNs for each ROI method (P<0.001). Round ROI proved the most accurate method in characterizing TGCNS. CONCLUSION: Interobserver variability in ADC measurement is excellent, irrespective of the ROI shape. Multiple, small round ROIs and round ROI proved the more accurate methods for ADC measurement in the characterization of TGCNs and in the differentiation between seminomas and NSGCNs, respectively.
Authors: Gamal Anton Wakileh; Christian Ruf; Axel Heidenreich; Klaus-Peter Dieckmann; Catharina Lisson; Vikas Prasad; Christian Bolenz; Friedemann Zengerling Journal: World J Urol Date: 2021-11-15 Impact factor: 4.226