Which histological finding in resected kidney indicated Bilateral Wilm's tumor?

Ans. (b) Nephrogenic rests(Ref: Robbins 9th/pg 479- 481)Nephrogenic restsThey are putative precursor lesions of Wilms tumorsPatients with presence of nephrogenic rests in the resected specimen, are at an increased risk of developing Wilms tumors in the contralateral kidney and require frequent and regular surveillance.