MRI of Metanephric Adenoma

Abstract

We report the imaging findings of metanephric adenoma. US examination showed a protruding hypoechoic mass at the right kidney. CT revealed a well defined isodense mass with calcifications. On angiography, neither neovascularization nor tumor staining was revealed at all. The T1-weighted MR images showed a hypointense mass that was slightly hyperintense on T2-weighted MR images. Histologically, the tumor was metanephric adenoma.

Metanephric Adenoma of the Kidney: Case Report and Review of the Literature

“…Many of these tumors had been diagnosed previously as nephroblastoma or renal cell carcinoma (4) or have been published under different diagnoses but fitted in the histological image of Mostofi and Brisigotti [5]. Since 1995, 39 cases of tumors with the typical morphology have been reported under the term of metanephric adenoma [3,[9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”

Renal Metanephric Adenoma Mimicking Papillary Renal Cell Carcinoma on Computed Tomography: A Case Report

“…Jinzaki et al [1] reported that attenuation during both the CMP and late NP was higher in their 2 cases of renal MA than in PRCC, and that higher attenuation during each phase may be an important difference between renal MA and PRCC. To clarify the enhancement pattern of renal MA on multiphase enhanced CT, we reviewed previously reported cases [1,5,6,7]. Table 1 summarizes the enhancement patterns of 7 renal MAs on multiphase enhanced CT.…”

CT and ultrasound findings of metanephric adenoma: a report of two cases and literature review

“…The imaging features of MA have been reported in some cases [6][7][8][9]. However, no typical sonographic or radiological features of MA have been identified.…”

“…Small punctate calcifications have been reported in some cases [3,6]. The T 1 weighted MRI showed a hypo-or isointense mass that was slightly hyperintense on T 2 weighted MRI [4,9]. MA must always be considered in the differential diagnosis of renal tumours in children and adults, independent of their size, particularly when the tumours appear as well-defined rounded lesions.…”

“…Until now it was thought to have a benign course. In the English language literature no more than 100 cases of MAs have been reported, and in only a few have the imaging findings been well illustrated [2][3][4][5][6][7][8][9][10][11][12][13]. We report two cases of MA in a 17-year-old and a 30-year-old female and describe their appearances on CT and ultrasonography.…”