Cecilia Besa1,2, Stephen Ward3, Yong Cui2,4, Guido Jajamovich2, Michelle Kim5, Bachir Taouli1,2. 1. Department of Radiology, Body MRI, Icahn School of Medicine at Mount Sinai, New York, USA. 2. Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA. 3. Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, USA. 4. Department of Radiology, Peking University Cancer Hospital & Beijing Cancer Hospital, Beijing, China. 5. Department of Medicine, Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, USA.
Abstract
PURPOSE: To assess the value of apparent diffusion coefficient (ADC) measured with diffusion-weighted imaging (DWI) and enhancement ratios (ER) measured with contrast-enhanced T1-weighted imaging (CE-T1WI) for the characterization of histopathologic tumor grade of neuroendocrine tumor liver metastases (NETLM). MATERIALS AND METHODS: Twenty-two patients with pathology-proven NETLM and pretreatment 1.5 Tesla (T) and 3T MRI including DWI were included in this Institutional Review Board-approved retrospective study. ADC histogram parameters, including mean, minimum (min), skewness, and kurtosis as well as ER, were computed for all lesions. Tumor grading was based on the World Health Organization 2010 classification. Kruskal-Wallis and Mann-Whitney test were used to assess for differences in ADC and ER between different tumor grades. MRI parameters were correlated with pathologic findings using Spearman correlation test. Receiver operating characteristic analysis was performed to determine optimum thresholds for predicting tumor grade. RESULTS: Forty-eight NETLM (mean size 3.5 cm) were analyzed with the following grade distribution: G1 (n = 25), G2 (n = 16), and G3 (n = 7). ADC-mean (×10-3 mm2 /s) of G3 tumors (0.87 ± 0.43) was significantly lower than that of G1 (1.47 ± 0.63) and G2 (1.27 ± 0.63; P = 0.042). A weak significant negative correlation was observed between ADC and tumor grade (ADC-mean: r = -0.33, P = 0.02; ADC-min: r = -0.37, P = 0.01) and Ki-67 (ADC-mean: r = -0.31, P = 0.03; ADC-min: r = -0.39, P = 0.007). AUROC, sensitivity and specificity of ADC-mean/ADC-min/ER (measured at the early arterial phase) for differentiation of G3 versus G1-G2 were 0.80/0.76/0.67, 100%/50%/70%, and 68.4%/84.2%/66.6%, respectively. CONCLUSION: ADC is a promising marker for characterization of histopathologic grade of NETLM. These results should be confirmed in a prospective study. J. Magn. Reson. Imaging 2016;44:1432-1441.
PURPOSE: To assess the value of apparent diffusion coefficient (ADC) measured with diffusion-weighted imaging (DWI) and enhancement ratios (ER) measured with contrast-enhanced T1-weighted imaging (CE-T1WI) for the characterization of histopathologic tumor grade of neuroendocrine tumor liver metastases (NETLM). MATERIALS AND METHODS: Twenty-two patients with pathology-proven NETLM and pretreatment 1.5 Tesla (T) and 3T MRI including DWI were included in this Institutional Review Board-approved retrospective study. ADC histogram parameters, including mean, minimum (min), skewness, and kurtosis as well as ER, were computed for all lesions. Tumor grading was based on the World Health Organization 2010 classification. Kruskal-Wallis and Mann-Whitney test were used to assess for differences in ADC and ER between different tumor grades. MRI parameters were correlated with pathologic findings using Spearman correlation test. Receiver operating characteristic analysis was performed to determine optimum thresholds for predicting tumor grade. RESULTS: Forty-eight NETLM (mean size 3.5 cm) were analyzed with the following grade distribution: G1 (n = 25), G2 (n = 16), and G3 (n = 7). ADC-mean (×10-3 mm2 /s) of G3 tumors (0.87 ± 0.43) was significantly lower than that of G1 (1.47 ± 0.63) and G2 (1.27 ± 0.63; P = 0.042). A weak significant negative correlation was observed between ADC and tumor grade (ADC-mean: r = -0.33, P = 0.02; ADC-min: r = -0.37, P = 0.01) and Ki-67 (ADC-mean: r = -0.31, P = 0.03; ADC-min: r = -0.39, P = 0.007). AUROC, sensitivity and specificity of ADC-mean/ADC-min/ER (measured at the early arterial phase) for differentiation of G3 versus G1-G2 were 0.80/0.76/0.67, 100%/50%/70%, and 68.4%/84.2%/66.6%, respectively. CONCLUSION: ADC is a promising marker for characterization of histopathologic grade of NETLM. These results should be confirmed in a prospective study. J. Magn. Reson. Imaging 2016;44:1432-1441.
Authors: Wouter Mebis; Annemiek Snoeckx; Bob Corthouts; Haroun El Addouli; Simon Nicolay; Astrid Van Hoyweghen; Maarten Spinhoven; Bart Op de Beeck Journal: J Belg Soc Radiol Date: 2020-01-30 Impact factor: 1.894