Unilateral renal cystic disease in the right kidney.

A 51-year-old man was referred from oncology department with incidental detection of unilateral multiple renal cysts on computed tomography (CT) during evaluation of colon cancer (Figure-1). Abdominal CT revealed enlarged right kidney with variable-sized round, well-marginated multiple cysts without capsule formation or solid content, while the left kidney was normal. Family history was negative for kidney disease. Ultrasound imaging of the parents, five adult siblings, one son and two daughters showed normal kidneys. He received chemotherapy with 5-flurouracil plus leucovorin after laparoscopic right hemicolectomy for colon cancer. The relevant laboratory data were as follows: white blood cell count, 7000/mm3; hemoglobin level, 15.9 g/dL; platelet count, 174,000/mm3; blood urea nitrogen level, 15.5 mg/dL; creatinine level, 0.8 mg/dL and no proteinuria or hematuria. We did not introduce specific therapy for the unilateral cyst and follow-up was made with magnetic resonance image (MRI) six month after hemicolectomy. The exam showed numerous cysts in the right kidney with no changes according to previous CT (Figure-2). This patient has unilateral renal cystic disease (URCD), a rare entity characterized by multiple cysts in one kidney or a portion of one