Multicystic nephroma--report of two cases.

Multicystic Nephroma (MCN) is an uncommon renal pathology, characterized by the presence of usually unilateral circumscribed focal lesion consisting of multiple thin walled cysts. The etiology and pathogenesis of multicystic nephroma is not clear, and it is considered as a neoplastic lesion by many authors. To the best of our knowledge it has not yet been reported from India. We report first two pediatric cases of MCN from India. Computerized Tomography (CT) scan in both the cases revealed a unilateral cystic lesion in the lower pole of kidney. Keeping in mind the age, clinical presentation and radiological appearance, a possibility of Wilm 's tumour with cystic change could not be ruled out preoperatively and both children underwent nephrectomy. Since MCN has a benign behaviour it must be differentiated from focal cystic neoplastic lesions, including Cystic Partially Differentiated Nephroblastoma (CPDN), which has a low but distinct capability for local recurrence, and from Wilm's tumour with cystic change. Segmental form of unilateral renal dysplasia also needs to be considered in the clinical and radiological differential diagnoses.