426 Background: To assess the utility of 5.0-Tesla non-enhanced magnetic resonance imaging (5T NE MRI) for preoperative evaluation of renal tumor patients, particularly with renal insufficiency, as an alternative to contrast-enhanced computed tomography (CECT). Methods: We enrolled participants in a sequential cohort based on their renal status. Initially, eighteen patients with renal insufficiency (glomerular filtration rate < 90 mL/min/1.73 m²) underwent a 5T NE MRI for preoperative assessment. Afterward, 68 patients with normal renal function underwent both 5T NE MRI and CECT preoperatively. Imaging diagnoses, tumor staging, and renal arterial visualization were evaluated. Results: In patients with renal insufficiency, 5T NE MRI correctly identified 16 of 17 (94.1%) renal cell carcinoma (RCC) cases and accurately staged 92.9% of T 1–2 stage RCC (13/14) and 100% of T 3–4 stage RCC (3/3). Among patients with normal renal function, 5T NE MRI demonstrated higher diagnostic accuracy for RCC than CECT (59/59, 100% versus 53/59, 89.8%, p = 0.031) and correctly diagnosed all lipid-poor angiomyolipoma cases (2/2 versus 0/2 on CT). 5T NE MRI provided superior accuracy for identifying 57/57 T 1–2 stage (100%) versus 50/57 (87.7%) on CECT (p = 0.016) with no overstaging, while CECT overstaged 7 cases. Both 5T NE MRI and CECT achieved 100% visualization of grade 3 renal arteries. Conclusions: 5T NE MRI offers high diagnostic accuracy and staging, additionally providing grade 3 vascular visualization. It yields excellent diagnostic performance for renal tumors comparable to CECT, without the need for nephrotoxic contrast or radiation. It is especially beneficial for patients with renal insufficiency as a promising alternative in preoperative evaluation. CECT, n/N (%) 5T NE MRI, n/N (%) P-value Diagnostic Accuracy RCC 53/59 (89.8) 59/59 (100.0) 0.031 AML 7/9 (77.8) 9/9 (100.0) 0.500 Lipid-poor AML 0/2 2/2 T stage Accuracy T 1-2 Accordance 50 57 0.016 T 3-4 Accordance 2 2 - Vessel Grade b Grade ≤3 68 (100.0) 68 (100.0) - Grade ≥4 61 (88.1) 46 (64.3) <0.001
Chen et al. (Sun,) studied this question.