Renal masses represent a really common finding in a radiological daily practice; these lesions can be solid or cystic, benign or malignant, and sometimes the exact diagnosis can be difficult. The aim of our study was to compare multi-slice CT and high-field MR images for the diagnostic characterization of renal masses.

We studied 21 patients with ultrasonographic evidence of renal masses. The total of renal masses were 23, of which the majority (74%; n=17) were malignant tumors (clear cell renal cell carcinoma=10, chromophobe renal cell carcinoma=2, squamocellular carcinoma=1, urothelial carcinoma=2, lymphoma=1, Wilms’ tumor=1), and the remaining 6 lesions (26%) were benign (simple cyst=1, hemorrhagic cyst=1, lipoma=1, pyelonephritis=2, oncocytoma=1). All patients underwent pre- and post-contrast multi-slice CT and high-filed (3.0 Tesla) MR imaging studies. The images were evaluated in a double blind study by two expert radiologists....

The size data of renal masses measured on CT and MR images are illustrated in Table (Fig.1). CT and MR showed comparable diagnostic accuracy for lesion identification and characterization with no statistically significant differences: CT/MR accuracy for lesion identification=100%/100%, CT/MR accuracy for lesion differentiation between benign and malignant nature=95%/95%, CT/MR accuracy for lesion margin features=95%/95%, CT/MR accuracy for fat infiltration=82%/83%, CT/MR accuracy for vascular invasion=95%/95%; only in a case of oncocytoma, CT and MR were both inaccurate because the lesion was classified as malignant, since...

MR imaging represents a valid diagnostic alternative for lesion identification and characterization compared to CT in the diagnostic evaluation of patients with renal masses. The results of our study show a comparable diagnostic accuracy between CT and MR in the identification of renal masses as well as in the differentation between benign and malignant lesions similarly evaluating margin regularity, fat infiltration and vascular invasion. In conclusion, the high-field intensity of new MR equipments allows good imaging quality in the evaluation of the renal masses avoiding...

Israel GM, Bosniak MA. How i do it: evaluating renal masses. Radiology. 2005; 236: 441-450; Israel GM, Hindman N, Bosniak MA.Evaluation of cystic renal masses: comparison of CT and MR imaging by using the Bosniak classification system. Radiology. 2004; 231: 365–371; Dyer R, DiSantis DJ, McClennan BL. Simplified imaging approach for evaluation of the solid renal mass in adults. Radiology. 2008; 247: 331-343; Blitman NM, Berkenblit RG, Rozenblit AM, Levin TL. Renal medullary carcinoma: CT and MRI features. Am J Roentgenol. 2005; 185: 268-72; Pallwein-Prettner...