[Characterization and staging of XXXX : significance of MRI diagnostics].

@entity1 @entity8 @entity5409 @entity5 @entity189 @entity1358 @entity703
PURPOSE: Retrospective evaluation of MRI in the diagnosis of renal masses and determination of the correlation of MRI with histology or follow-up. MATERIALS AND METHODS: 46 consecutive @entity1 (13 female, 33 male, mean age 64.7 yrs) with suspected @entity703 were examined with a 1.5 T MR scanner using a standardized protocol (TSE T2fs, 2DGRE T1, dynam. ce3DGRE T1fs, ce2DGRE T1fs, ce3DGRE urogram). RESULTS: 142 @entity8 were found with diameters of < 2 cm up to 14 x 18 cm. A primary classification as solid and @entity5409 was performed according to MRI criteria. In 29 cases we found lesions bilaterally, in 17 @entity1 only in one kidney, and in four cases we found multifocal @entity703 unilaterally (n = 3) or bilaterally (n = 1). In 22 @entity1 with @entity703 , @entity5409 could be seen as well. In 19 cases these were uncomplicated cysts, and in 3 cases these were complicated cysts. 35/43 lesions were histologically proven solid vascularized @entity5 (29 @entity1358 , 6 @entity189 ), five additional masses with @entity5 signs in MRI appeared to be progressive during follow-up thus suggesting @entity5 , and one case was a multifocal bilateral @entity703 . 3/43 lesions were initially reported as being suspected of @entity5 but were proven during follow-up or histologically to be benign. @entity5 thrombus was depicted in MRI in the renal vein in 5 cases, stretching into the IVC in 4 cases and proven histologically in 4 and 3 cases, respectively. Of these solid masses, 99 @entity5409 could be differentiated clearly in MRI (88 simple cysts, 11 complicated cysts) that remained unchanged during follow-up (6 - 65 months) or were proven to be cysts histologically. In 17 cases these cysts were bilateral, in 19 cases unilateral, and 33 kidneys showed multicystic changes. In characterizing renal masses, MRI showed a positive predictive value of 93 % for the diagnosis of a @entity5 . The T-stage of histologically proven @entity1358 using MRI was correct in 89 %. CONCLUSIONS: MRI is a valid modality for characterizing and staging renal masses using a suitable sequence protocol that includes dynamic ce studies. @entity5 invasion can be depicted safely. MRI can be employed alternatively to state-of-the-art ceCT and additionally to CT in unclear cases.
