1. Persistent metanephric Blastemas after 36 weeks of gestational age are called nephrogenic rests

2. We report two cases of metanephric adenomas and compare their immunophenotype with a papillary adenoma.

3. The differential diagnosis between papillary adenoma or papillary carcinoma type 1 and metanephric adenoma of the kidney can be challenging in single cases.

4. Metanephric Blastema (or metanephrogenic Blastema) is one of the two embryological structure that gives rise to the kidney, the other one being the ureteric bud.

5. A wandering ureteral bud may cross the midline to the contralateral side and diffuse with the contralateral metanephric Blastema, rather than the same side Blastema, resulting in the …

6. Bilateral metanephric adenoma of the kidney is an exceptional entity (to our knowledge only one case has been reported in the literature) which renders the differential diagnosis with bilateral cancer of the kidney difficult.