Assessment of Imaging Findings of Renal Carcinoma Subtypes with 3.0T MRI

Abstract

Background: The prevalence of renal masses has escalated as a result of the augmented utilization of cross-sectional imaging techniques. The approach to managing renal masses may exhibit variability contingent upon the subtype of renal cell carcinoma (RCC).   

Aim: This research aimed to distinguish between clear cell and papillary RCCs, utilizing dynamic contrast magnetic resonance imaging  (MRI) and diffusion‑weighted imaging (DWI). 

Materials and Methods: The study assessed the MR images of 112 patients with RCC. Two  radiologists independently analyzed tumor size, vascular involvement, signal characteristics in T1- and T2-weighted sequences, the  presence of hemosiderin, both microscopic and macroscopic fat content, enhancement patterns, and apparent diffusion coefficient (ADC)  values derived from b‑values of 1000 s/mm². 

Results: Seventy patients had clear cell RCC, and 42 had papillary. In the clear cell  RCC, microscopic fat content was significantly higher than the papillary RCC (P < 0.001). However, in papillary RCC, hemosiderin content  was substantially greater (P = 0.001). On T2-weighted MR images, clear cell RCCs were usually hyperintense, while papillary RCCs were  hypointense (P < 0.001). Even though the rapid enhancement pattern was observed in clear cell RCCs, the progressive enhancement  pattern was more prevalent in papillary RCCs (P < 0.001). 

Conclusion: Hyperintensity on T2-weighted images, microscopic fat content,  and rapid enhancement pattern may be indicative of clear cell RCC, whereas hypointensity on T2-weighted images, hemosiderin content,  and a progressive contrast pattern may be diagnostic for papillary RCC.