Application of diffusion kurtosis tensor MR imaging in characterization of renal cell carcinomas with different pathological types and grades

Abstract

Background To probe the feasibility and reproducibility of diffusion kurtosis tensor imaging (DKTI) in renal cell carcinoma (RCC) and to apply DKTI in distinguishing the subtypes of RCC and the grades of clear cell RCC (CCRCC). Methods Thirty-eight patients with pathologically confirmed RCCs [CCRCC for 30 tumors, papillary RCC (PRCC) for 5 tumors and chromophobic RCC (CRCC) for 3 tumors] were involved in the study. Diffusion kurtosis tensor MR imaging were performed with 3 b-values (0, 500, 1000s/mm2) and 30 diffusion directions. The mean kurtosis (MK), axial kurtosis (Ka), radial kurtosis (Kr) values and mean diffusity (MD) for RCC and contralateral normal parenchyma were acquired. The inter-observer agreements of all DKTI metrics of contralateral renal cortex and medulla were evaluated using Bland-Altman plots. Statistical comparisons with DKTI metrics of 3 RCC subtypes and between low-grade (Furman grade I ~ II, 22 cases) and high-grade (Furman grade III ~ IV, 8 cases) CCRCC were performed with ANOVA test and Student t test separately. Receiver operating characteristic (ROC) curve analyses were used to compare the diagnostic efficacy of DKTI metrics for predicting nuclear grades of CCRCC. Correlations between DKTI metrics and nuclear grades were also evaluated with Spearman correlation analysis. Results Inter-observer measurements for each metric showed great reproducibility with excellent ICCs ranging from 0.81 to 0.87. There were significant differences between the DKTI metrics of RCCs and contralateral renal parenchyma, also among the subtypes of RCC. MK and Ka values of CRCC were significantly higher than those of CCRCC and PRCC. Statistical difference of the MK, Ka, Kr and MD values were also obtained between CCRCC with high- and low-grades. MK values were more effective for distinguishing between low- and high- grade CCRCC (area under the ROC curve: 0.949). A threshold value of 0.851 permitted distinction with high sensitivity (90.9%) and specificity (87.5%). Conclusion Our preliminary results suggest a possible role of DKTI in differentiating CRCC from CCRCC and PRCC. MK, the principle DKTI metric might be a surrogate biomarker to predict nuclear grades of CCRCC. Trial registration ChiCTC, ChiCTR-DOD-17010833, Registered 10 March, 2017, retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=17559.

Diffusion kurtosis versus diffusion-weighted MRI in differentiating clear cell renal cell carcinoma and renal angiomyolipoma with minimal fat: a comparative study

“…It has been shown to offer superior sensitivity over conventional DTI [12]. An appealing aspect of the incorporation of DKI into routine clinical practice is that it can be performed in a straightforward manner, given that the sequence is performed in essentially the same manner as a standard DWI sequence [13], aside from the need for generally higher b values.…”

Evaluation of calculation processes of apparent diffusion coefficient subtraction method (ASM) imaging

“…The recently developed DK imaging technique is one RD imaging technique that is based on the principle of measuring the degree of non-Gaussian distribution of water molecule diffusion [23,24]. It has been previously reported that the DK imaging technique has conferred high sensitivity and specificity for detecting tumors in the brain, kidney, liver and prostate, in addition to other diseases, including cerebrovascular infarction, Alzheimer's disease, mild cognitive impairment, Parkinson's disease, multiple sclerosis and aging-related changes in the brain microstructure [8,[25][26][27][28].…”

Diffusion-Weighted MRI in the Genitourinary System

“…In a meta-analysis of 1126 renal lesions from 13 studies, clear cell renal cell carcinomas (RCC) demonstrated higher ADC values than non-clear cell RCCs, low-fat angiomyolipomas, papillary RCCs, and chromophobe RCCs, but lower ADC values than oncocytomas [ 93 ]. Although these results were recently confirmed using either ADC [ 92 ] or kurtosis tensor MR imaging—a more advanced type of DWI analysis [ 94 ]—the moderate sensitivity and specificity reported by these works may be insufficient for DWI to be a reliable single test to differentiate RCC subtypes [ 93 ]. In a study of 46 patients with Von Hippel–Lindau (VHL) disease, ADC at baseline was negatively correlated with the volume doubling time of 100 clear cells RCCs [ 95 ].…”