Preoperatively evaluating the correlation between pathological grades and blood oxygenation level-dependent MRI in clear cell renal cell carcinomas

Abstract

Rationale and objectives: To assess whether r(2)* values can be used to determine the nuclear grade of clear cell renal cell carcinomas (CRCC).

Materials and methods: A total of 26 patients with pathologically proven CRCCs underwent blood oxygen level-dependent magnetic resonance imaging. r(2)* values were determined for the solid components of CRCC lesions. Histological nuclear grade was determined for each lesion. All patients were divided into low- and high-grade groups. r(2)* values were compared between different grades and between low- and high- grade groups. Receiver operating characteristic curve was drawn to establish the cutoff point for r(2)* values. The correlation between r(2)* values and pathological groups was assessed.

Results: Low-grade group (grades I + II) contained 17 cases and high-grade group (grades III + IV) contained nine cases. The intraclass correlation coefficient for r(2)* values was 0.89. Significant difference was seen between different grades (P < .005). r(2)* values of the high-grade group were higher than the low-grade group (P < .005). A sensitivity of 78% and a specificity of 100% were achieved with a cutoff of 31.87 seconds(-1). r(2)* values directly correlated with pathological groups (P < .005).

Conclusion: r(2)* values of CRCCs could be employed as a noninvasive biomarker to help classify the nuclear grade of CRCC.