Radiologic-Pathologic Analysis of Contrast-enhanced and Diffusion-weighted MR Imaging in Patients with HCC after TACE: Diagnostic Accuracy of 3D Quantitative Image Analysis

Abstract

Purpose To evaluate the diagnostic performance of three-dimensional (3D) quantitative enhancement-based and diffusion-weighted volumetric magnetic resonance (MR) imaging assessment of hepatocellular carcinoma (HCC) lesions in determining the extent of pathologic tumor necrosis after transarterial chemoembolization (TACE). Materials and Methods This institutional review board–approved retrospective study included 17 patients with HCC who underwent TACE before surgery. Semiautomatic 3D volumetric segmentation of target lesions was performed at the last MR examination before orthotopic liver transplantation or surgical resection. The amount of necrotic tumor tissue on contrast material–enhanced arterial phase MR images and the amount of diffusion-restricted tumor tissue on apparent diffusion coefficient (ADC) maps were expressed as a percentage of the total tumor volume. Visual assessment of the extent of tumor necrosis and tumor response according to European Association for the Study of the Liver (EASL) criteria was performed. Pathologic tumor necrosis was quantified by using slide-by-slide segmentation. Correlation analysis was performed to evaluate the predictive values of the radiologic techniques. Results At histopathologic examination, the mean percentage of tumor necrosis was 70% (range, 10%–100%). Both 3D quantitative techniques demonstrated a strong correlation with tumor necrosis at pathologic examination (R2 = 0.9657 and R2 = 0.9662 for quantitative EASL and quantitative ADC, respectively) and a strong intermethod agreement (R2 = 0.9585). Both methods showed a significantly lower discrepancy with pathologically measured necrosis (residual standard error [RSE] = 6.38 and 6.33 for quantitative EASL and quantitative ADC, respectively), when compared with non-3D techniques (RSE = 12.18 for visual assessment). Conclusion This radiologic-pathologic correlation study demonstrates the diagnostic accuracy of 3D quantitative MR imaging techniques in identifying pathologically measured tumor necrosis in HCC lesions treated with TACE.

3D Quantitative tumour burden analysis in patients with hepatocellular carcinoma before TACE: comparing single-lesion vs. multi-lesion imaging biomarkers as predictors of patient survival

“…The enhancing tumour volume (ETV) measurement was performed as in previous studies [11, 12]. Briefly, this was done as follows: The native T1 images were subtracted from the arterial-phase T1 images to remove the background signal.…”

Quantitative volumetric functional MR imaging: an imaging biomarker of early treatment response in hypo-vascular liver metastasis patients after yttrium-90 transarterial radioembolization

“…Furthermore, the software enabled easy and better reproducibility analysis of multiparametric MR imaging data compared to ROI-based axial measurements [15,24,28]. The presented data by Chapiro et al [29] provided multilayer proof of the precision of 3D quantitative perfusion and diffusion-weighted MR imaging when correlated with pathologic examination as a standard of Ref. [14][15][16].…”

The impact of antiangiogenic therapy combined with Transarterial Chemoembolization on enhancement based quantitative tumor response assessment in patients with hepatocellular carcinoma

“…qEASL validation to pathology and implications for patient care have been shown in previous work [1, 11]. To calculate qEASL, the pre-contrast phase images were registered to the corresponding arterial phase image (using Philips Fast Elastic Image Registration [FEIR] software) and subsequently subtracted from the arterial phase images to mitigate contribution of background enhancement and to isolate the image intensity component corresponding to enhancement induced by contrast agent [10].…”

“…A plethora of published data demonstrates that unidimensional measurements such as Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST (mRECIST), as well as bidimensional measurements like the World Health Organization (WHO) and the European Association for the Study of the Liver (EASL) criteria, are unreliable in the setting of TACE at an early time point [1, 9]. New 3D imaging biomarkers, such as the quantitative EASL [qEASL], have meanwhile been established to address the previously unmet need for robust tumor assessment techniques after TACE [1, 8, 10, 11]. However, they have not yet been tested in the framework of TACE combined with systemic therapy using anti-angiogenic agents such as bevacizumab.…”