Histogram Analysis of Diffusion Weighted Imaging at 3T is Useful for Prediction of Lymphatic Metastatic Spread, Proliferative Activity, and Cellularity in Thyroid Cancer

Abstract

Pre-surgical diffusion weighted imaging (DWI) is increasingly important in the context of thyroid cancer for identification of the optimal treatment strategy. It has exemplarily been shown that DWI at 3T can distinguish undifferentiated from well-differentiated thyroid carcinoma, which has decisive implications for the magnitude of surgery. This study used DWI histogram analysis of whole tumor apparent diffusion coefficient (ADC) maps. The primary aim was to discriminate thyroid carcinomas which had already gained the capacity to metastasize lymphatically from those not yet being able to spread via the lymphatic system. The secondary aim was to reflect prognostically important tumor-biological features like cellularity and proliferative activity with ADC histogram analysis. Fifteen patients with follicular-cell derived thyroid cancer were enrolled. Lymph node status, extent of infiltration of surrounding tissue, and Ki-67 and p53 expression were assessed in these patients. DWI was obtained in a 3T system using b values of 0, 400, and 800 s/mm2. Whole tumor ADC volumes were analyzed using a histogram-based approach. Several ADC parameters showed significant correlations with immunohistopathological parameters. Most importantly, ADC histogram skewness and ADC histogram kurtosis were able to differentiate between nodal negative and nodal positive thyroid carcinoma. Conclusions: histogram analysis of whole ADC tumor volumes has the potential to provide valuable information on tumor biology in thyroid carcinoma. However, further studies are warranted.

Intravoxel incoherent motion and ADC measurements for differentiating benign from malignant thyroid nodules: utilizing the most repeatable region of interest delineation at 3.0 T

“…The results of this study indicated that the repeatability of IVIM parameters is excellent when using W-L ROI analysis for thyroid nodules, providing a strong basic foundation for future multi-centre, large-sample studies as well as stratification research. These results revealed that the diffusion effect plays a major role in differentiating malignant thyroid nodules, which may be based on differences in the cell density and histopathologic features of benign and malignant thyroid nodules [18,35]. Some ADC and DKI studies with higher b values (1000 s/mm 2 to 2000 s/mm 2 ) have shown the role of diffusion in differentiating benign from malignant thyroid nodules [36,37].…”

“…The results derived from the S-S ROI analysis showed variability in both sensitivity and specificity [6,7]. Whereas some studies have used W-L ADC imaging or histograms to evaluate thyroid nodules and distinguish different types of malignant thyroid nodules or benign nodules from malignant nodules [18][19][20], this study used IVIM with W-L ROI delineation that included cystic, necrotic and micro-calcified components of thyroid nodules, and the results demonstrated that all parameters had better reproducibility and repeatability than those of S-S ROI delineation. Notably, the perfusionrelated parameters (f and D*) derived from the W-L ROIs showed excellent intra-and interobserver agreement, which may be related to the use of ROIs across whole tumours, thus minimizing the intra-and interobserver differences in ROI delineations.…”

“…Accurate image segmentation is the premise of radiomics analyses. Most previous studies adopted a manual single-section (S-S) region of interest (ROI) analysis for the quantitative assessment of thyroid nodules to avoid necrotic, cystic and micro-calcified areas [6,7,[14][15][16][17], while few studies used whole-lesion (W-L) ROI analyses [12,[18][19][20]. Notably, the appropriate ROI size and positioning have considerable influence on the quantitative parameters of tumour and interobserver variability [21,22].…”

Performance of Diffusion and Perfusion MRI in Evaluating Primary Central Nervous System Lymphomas of Different Locations

“…Previous studies have shown a significant inverse correlation between tumor cell density and ADC value in PCNSLs, suggesting ADC to be a surrogate marker for tumor proliferation and Ki-67 index [23][24][25]. Barajas et al [11] reported that ADC measurements could predict clinical prognosis in patients with PCNSLs.…”

Quantitative Assessment of Thyroid Nodules Using Dual-Energy Computed Tomography: Iodine Concentration Measurement and Multiparametric Texture Analysis for Differentiating between Malignant and Benign Lesions

“…Heterogeneity in the malignant tissues is recognized to reflect cellularity, necrosis, and angiogenesis, which are associated with disorders of attenuation [33]. Previous studies demonstrated that texture analysis of images obtained from US and MRI is useful for distinguishing between benign thyroid nodules and malignancies with less-uniform texture parameters, classifiers, and applications [15,16,[34][35][36]. Since thyroid nodules are often detected by CT scan before performing further US, with texture analysis using DECT, unnecessary further examinations of the thyroid lesions can be potentially prevented.…”