Acquired Cystic Disease-associated Renal Cell Carcinoma with Unusual Gross Finding Similar to Autosomal Dominant Polycystic Kidney Disease: A Case Report

초록

Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a recently defined unique subtype of renal cell carcinoma which has been reported only in patients with acquired cystic kidney disease. We experienced a case of ACD-RCC in 40-year-old male. The patient had a medical history of peritoneal dialysis for 15 years due to chronic renal failure. Abdomen-pelvic computed tomography revealed multiple cysts in bilateral kidney with calcification of the cyst wall and severe adhesion of small intestine. Radical nephrectomy of left kidney was performed. The kidney was enlarged, measuring 28X17X12 cm and weighing 2,300 gram. The renal parenchyma was near totally replaced by various-sized multiple cysts with calcified wall (cyst size: up to 11cm). There was no definite tumor mass. Histologically, several tumor foci were found between the cysts, measuring 2X1.5 cm in the largest one. The tumor showed variegated growth pattern including tubule-papillary, cribriform, micro and microcyst, and alveolar architecture. Inter- and intracellular microlumens were noted in the tumor cells. The tumor cells had small distinct nucleoli, abundant eosinophilic cytoplasm. Some oxalate crystals were found within the tumor. Hemosiderin pigments were frequently found. The tumor cells were positive for PAX8, AMACR, and CD10, but negative for cytokeratin 7. Some part of the cyst-lining cells showed similar features of the tumor cells such as small distinct nucleoli, abundant eosinophilic cytoplasm inter-and intracellular microlumens. They also showed same immunohistological findings as tumor cells. The gross finding of our case is similar to that of autosomal dominant polycystic kidney disease (ADPKD) which show variable sized (usually several centimeters), numerous randomly distributed cysts throughout both kidneys. In contrast, the gross findings of acquired cystic disease show multiple cysts, from mm to several centimeters. The kidney size and both number and size of cysts are smalle