Diagnostic value of multimodal MRI quantitative and qualitative analysis in high and low grade renal clear cell carcinoma

Objective To explore the diagnostic value of 3.0T MRI sequence features and parameters for high and low grade clear cell renal cell carcinoma (ccRCC). Methods A total of 89 ccRCC patients who were pathologically diagnosed in the Affiliated Hospital of Xuzhou Medical University from January 2012 to April 2020 were enrolled and their pathological data, preoperative renal MRI and enhanced MRI were retrospectively analyzed. According to the Fuhrman nuclear grade system, the patients were divided into two groups: a low grade group (gradesⅠand Ⅱ,n=70) and a high grade group (gradesⅢ and Ⅳ, n=19). Their incidences of pseudocapsule, cystic degeneration, necrosis, hemorrhage, calcification and fibrous cord, vein thrombosis, renal sinus and pefinephfic invasion, lymphadenopathy, and metastasis were statistically analyzed. The difference in DWI signal intensity of the lesion, the enhancement degree and method were recorded. The maximum diameter of tumor and the apparent diffusion coefficient value (ADC value) were also measured. Two-sample t-test, Ch-squared test and the receiver operating curve (ROC) were used to evaluate the MRI date between two groups. Results According to MRI images, there were statistically differences in the maximum tumor diameter, necrosis, vein thrombosis, renal sinus and pefinephfic invasion, lymphadenopathy, metastasis, DWI signal intensity, and medullary phase enhancement between the high and low grade groups (P<0.05). The corresponding areas under the curve (AUC) were: 0.816, 0.638, 0.692, 0.665, 0.737, 0.658, 0.752, and 0.661. There were no statistical differences in cystic degeneration, hemorrhage, calcified cord, pseudocapsule, and enhancement mode between the two groups (P>0.05). The ADC value of the low grade group was significantly higher than the ADC value of the high grade group (P<0.05), and the AUC was 0.830. Among the different diagnostic combinations, the AUC of the combination of ADC value, tumor maximum diameter, and medullary phase enhancement was 0.902, with a sensitivity of 73.7% and a specificity of 92.2%. Conclusions Qualitative and quantitative analysis of multimodal MRI can differentiate and diagnose high and low grade ccRCC. The ADC value combined with the maximum diameter and enhancement degree are the most effective in the diagnosis of high grade ccRCC, which can provide reference for clinical practice.