Another study of 33 cystic lesions imaged with both 1.5T and 3.0T MRI showed that there is a greater tendency to upgrade cyst complexity and Bosniak cyst category at 3.0T than at 1.5T and thus suggested that serial follow-up of cystic renal lesions be performed at constant field strength [58]. Solid Renal Masses Other than AMLs with macroscopic fat, MRI cannot yet reliably differentiate benign from malignant renal tumors. However, several MRI features have been reported to be useful for suggesting types of solid renal tumors. In one multiparametric MRI study, lipid-poor AMLs were characterized by higher T1 signal intensity and lower T2 signal intensity compared to normal renal cortex and by greater arterial-to-delayed enhancement ratio than RCC [59]. Another study showed that the combination of low T2 signal and signal drop on chemical-shift imaging is specific for lipid-poor AMLs but lacks sensitivity, and the combination of low T2 signal intensity and high area under the contrast-enhanced MRI curve is sensitive and specific for lipid-poor AMLs [60]. Although both papillary RCC and lipid-poor AMLs can have low signal intensity on T2-weighted images, the presence of intratumoral hemorrhage seen on T1-weighted images was suggested to be a specific feature of papillary RCC [61]. Nonetheless, MRI findings of lipid-poor AMLs overlap with various RCC subtypes and remain difficult to prospectively diagnose [60]. Indeterminate Renal Mass diagnostic algorithm had diagnostic accuracy of 81% (88 of 109) and 91% (99 of 109) in the diagnosis of clear-cell RCC and papillary RCC, respectively, while achieving moderate to substantial inter-reader agreement among 7 radiologists [64]. MRU There is no relevant literature regarding the use of MRU in the evaluation of indeterminate renal masses. Radiography Intravenous Urography There is no relevant literature regarding the use of IV urography (IVU) in the evaluation of indeterminate renal masses.
Indeterminate Renal Mass. Another study of 33 cystic lesions imaged with both 1.5T and 3.0T MRI showed that there is a greater tendency to upgrade cyst complexity and Bosniak cyst category at 3.0T than at 1.5T and thus suggested that serial follow-up of cystic renal lesions be performed at constant field strength [58]. Solid Renal Masses Other than AMLs with macroscopic fat, MRI cannot yet reliably differentiate benign from malignant renal tumors. However, several MRI features have been reported to be useful for suggesting types of solid renal tumors. In one multiparametric MRI study, lipid-poor AMLs were characterized by higher T1 signal intensity and lower T2 signal intensity compared to normal renal cortex and by greater arterial-to-delayed enhancement ratio than RCC [59]. Another study showed that the combination of low T2 signal and signal drop on chemical-shift imaging is specific for lipid-poor AMLs but lacks sensitivity, and the combination of low T2 signal intensity and high area under the contrast-enhanced MRI curve is sensitive and specific for lipid-poor AMLs [60]. Although both papillary RCC and lipid-poor AMLs can have low signal intensity on T2-weighted images, the presence of intratumoral hemorrhage seen on T1-weighted images was suggested to be a specific feature of papillary RCC [61]. Nonetheless, MRI findings of lipid-poor AMLs overlap with various RCC subtypes and remain difficult to prospectively diagnose [60]. Indeterminate Renal Mass diagnostic algorithm had diagnostic accuracy of 81% (88 of 109) and 91% (99 of 109) in the diagnosis of clear-cell RCC and papillary RCC, respectively, while achieving moderate to substantial inter-reader agreement among 7 radiologists [64]. MRU There is no relevant literature regarding the use of MRU in the evaluation of indeterminate renal masses. Radiography Intravenous Urography There is no relevant literature regarding the use of IV urography (IVU) in the evaluation of indeterminate renal masses.