Multifocal renal cell carcinoma associated with multiple simple renal cysts: A rare presentation

Abstract Simple renal cysts are the most common renal masses but the major concern is to differentiate a simple renal cyst from a complex cyst which may have foci of malignancy. However, this association is seen in 1% cases only. Most of the renal cysts are benign, asymptomatic and are usually treated conservatively. However, various cystic diseases are associated with renal cell carcinoma. Renal cysts with thickened, irregular septa and enhancement on contrast injection raise a suspicion of malignancy. We present a case of a 41 year old male who presented with renal cell carcinoma of left kidney with multiple simple renal cysts. Keywords: Multifocal RCC, Nephrectomy, Renal cyst, Renal cell carcinoma. Introduction Risk factors for Renal Cell Carcinoma (RCC) includes cystic diseases like Adult Polycystic Kidney Disease (APCKD), acquired cystic diseases, Von-Hippel Lindau (VHL) disease and tuberous sclerosis complex (TSC).[1],[2]Risk of RCC in ADPKD is not known exactly. On the other hand, risk of RCC in VHL patients is substantial and mortality rate is also high despite close follow-up. In tuberous sclerosis complex patient’s risk of development of RCC is far less as compared to the risk in VHL patients.[3]In cysts with a nodule, cystic tumour necrosis and intrinsically cystic neoplasms, the adjacent kidney tissue is mostly non-cystic. However, if multiple renal cysts are present, a cystic renal disease with a neoplastic diathesis should be considered and investigated. We present a case of 41 year old male patient who presented with RCC of left kidney in association with multiple simple renal cysts. Case Report A 41 year old male presented with lower back pain for 4 months. Ultrasound showed multiple solid and cystic lesions in left kidney and diagnosis was given as likely to be RCC. Left radical nephrectomy was done and renal specimen was received in histopathology measuring 8.5x7x6cm. External surface showed numerous cysts ranging in size f