Multilocular Cystic Renal Neoplasm of Low Malignant Potential in a Patient with Chronic Pyelonephritis and End-Stage Renal Disease: A Rare Case Report

Abstract Multilocular cystic renal neoplasm of low malignant potential (MCNLMP) is a rare subtype of clear cell carcinoma having an excellent prognosis. These tumors exhibit distinct morphology and comprises of multiple cysts separated by thin septa lined by clear cells with no expansile growth. These cysts, though rare in a setting of chronic pyelonephritis and end-stage renal disease, are usually diagnosed on radiography using the Bosniak classification. But in certain situations where cysts are not visible radiologically, a final diagnosis is made with the help of histopathology and immunohistochemistry only. We, hereby, report such a rare incidental case of MCNLMP diagnosed on histopathology in a nephrectomy specimen of an elderly male with chronic pyelonephritis and end-stage renal disease.