Predictive Analysis Of CT On The Grading Of T1a Renal Clear Cell Carcinoma

Objective: Nephron-sparing surgery is currently commonly used for renal clear cell carcinoma in stage T1a(tumor size?4 cm),but it may lead to higher recurrence and metastasis in patients with higher pathological grades.Preoperative pathological grading for T1 a renal clear cell carcinoma(RCCC)is very important.The relationship between different pathological grades of T1 a RCCC and CT scan of the kidney was retrospectively analyzed to predict the tumor's pathological grade based on the preoperative CT scan,and to contribute to selecting the appropriate therapeutic strategy.Methods: From June 2016 to April 2019,the 205 T1 a RCCC cases were collected from the First Hospital of China Medical University.There clinical data were complete,and they all had surgery.Fuhrman grading were used for pathological classification: 65 grade I,70 grade II,60 grade III,and 10 grade IV.The CT values of each phase during the CT scan were measured,and the comparison between groups and within groups was performed by analysis of variance and t test,and the pairwise comparison after analysis of variance was performed by SNK test.Univariate Logistic analysis was used to analyze the relationship between CT values at different phases and different pathological grades.The ability of CT value at different phases to predict pathological grades was compared by plotting the receiver operating characteristic curve(ROC).Chi-square test was used to compare the relationship between the age,tumor edges,calcification and pathological grade.The univariate and multifactor logistic regression methods were used to analyze the influence of the indicators on the preoperative grading.Results: The average CT value at each phase increased gradually with the increase of pathological grade,and the differences between groups were statistically significant(P <0.05).The comparison between groups was made at each phrase.The difference of mean CT value at each phase between level I,III and IV;between level II and IV were statistically significant.There were significant differences of the mean CT values between grade II and grade III at Non-enhanced CT and arterial phase,between grade III and grade IV at Non-enhanced CT(P <0.05).The pairwise comparisons among the other groups were not statistically significant.Grades I and II were combined into a low-grade group,and grades III and IV were combined into a high-grade group.The differences of mean CT values at each phase were statistically significant(P <0.05).The univariate logistic regression analysis showed statistically significant differences in mean CT values between the low-grade group and the high-grade group(P <0.05).The results of the ROC curve showed that the CT value of the Non-enhanced CT had a maximum area under the curve of 0.917,and the threshold is 36.25 HU,the sensitivity is 0.85,and the specificity is 0.80.The Logistic multivariate analysis corrected that the calcification inside the tumor could be used as an independent predictor of the pathological grade of RCCC.Conclusion: For the stage T1 a RCCC,the mean CT value of each phase during renal CT scan is positively correlated with pathological grade.It predicts high-grade RCCC that the average CT value higher than 36.25 HU at Non-enhanced CT,and/or higher than 134.5HU at arterial phase,and/or higher than 107.75 HU at parenchymal phase,and/or higher than 80.75 HU at wash out phase,and/or the calcification inside the tumor.The results can help predict the pathological grade of the tumor and provide some guidance for the treatment of patients with stage T1 a RCCC.