A Preliminary Study On CT Gemstone Spectral Imaging And Ki-67 Goint Evaluation Of Pathologic Grading In Clear Cell Renal Cell Carcinoma

Objective Discussing the correlation between CT spectroscopy imaging parameters and Ki-67 labeling index, to evaluate the biological behavior of CCRCC from an image perspective, and through the combination to assess the pathologic grading of CCRCC, which can provide the reference for preoperative therapy selection and prognostic evaluation.Methods 44 cases with CCRCC was analyzed by using retrospective way, all the patients underwent gemstone spectral imaging scans before operation and all tumor tissue pathologic specimens were confirmed by Ki-67 immunohistochemical staining after operation. The patients were divided into high differentiation and low differentiation group. High differentiation group includes 29 cases with grade I and II, and low differentiation group includes 15 cases with grade III and IV. The CT value ratio of CCRCC under 70 keV, the iodine concentration ratio and the spectrum curve slope of two group were measured by using region of interest (ROI) technique. Spectral characteristic parameters, spectrum curve and the expression of Ki-67 between two groups were compared.Results The Ki-67 LI of two groups was 5.55±4.31、19.20±10.80 (t=-5.99, P<0.01), and CT spectroscopy imaging parameters had a significantly negative correlation with Ki-67 LI in two phases. The CT value ratio of CCRCC under 70keV were 0.77±0.20, 0.63±0.21 (t=2.27, P<0.05) in cortex phase and 0.73±0.15,0.57±0.13 (t=3.29, P<0.01) in medulla phase. The iodine concentration ratio were 0.64±0.30,0.38±0.33 (t=2.61, P<0.05) in cortex phase and 0.58±0.20,0.39±0.21 (t=2.82, P<0.01) in medulla phase. The spectrum curve slope of two group were 3.37±1.55,1.62±1.94 (t=3.25, P<0.01) in cortex phase and 3.40±1.28,2.18±1.63 (t=2.72, P<0.01) in medulla phase. However, the water concentration ratio had no difference at each phase between the two groups (P>0.05). The 70 keV single energy ratio in the medulla phase provided the best combination of sensitivity (82.8%) and specificity (80%) in deciding the nuclear grading of CCRCC, and the area under the ROC curve was 0.870.Conclusion 1 The Ki-67 LI of high differentiation group was lower than low differentiation group, and it have important value to access malignant degree preoperatively of CCRCC.2 The CT value ratio of CCRCC under 70 keV, the iodine concentration ratio and the spectrum curve slope of two group in cortex and medulla phases had a significantly negative correlation with Ki-67 LI, and the evaluating methods combined GSI with Ki-67 have important diagnostic value for deciding tumor’s pathologic grading.