Cystic nephroma: A diagnostic dilemma

Cystic nephroma (CN) is a rare benign neoplasm of kidney with excellent prog­nosis. An accurate pre-operative diagnosis differentiating CN from other cystic renal malignan­cies may be impossible by clinical and radiological examination, and histopathological exami­nation provides the final diagnosis. This report describes two adult patients with large multi-locular cystic renal masses on imaging and the diagnosis of CN was clinched post-operatively by the ho­neycomb appearance of the cut specimen and the finding of multiple, non-communicating fluid filled cysts lined by cuboidal or flattened epithelial cells and absence of blastemal cells on mic­roscopy. Tumor diameter on cross sectional imaging remains the key parameter for treatment de­cisions in renal neoplasms, with nephrectomy being preferred for larger lesions.