Multilocular Renal Cysts with Renal Cell Carcinoma: Report of Four Cases

According to Bosniak's classification, renal cysts with moderate calcification, irregularmargins, and thickened enhanced septa should raise a suspicion of malignancy. Diagnosis ofmultilocular renal cysts depends on their histological features. Since 1951, it has generallybeen considered that a multilocular renal cyst can change from a benign lesion to one whichmay be combined with malignant change. According to a report from Japan, multilocularrenal cysts with renal cell carcinoma are uncommon, and the reported incidence was about9%. A radical nephrectomy was performed for malignant change. Herein, we present 4cases of multilocular cyst (Bosniak's class IV) with renal cell carcinoma and review therelated literature for their pathogenesis and management.