Papillary renal cell carcinoma radiographically mimicking massive calcification.

A 53-year-old male was referred to the Department of Urology, Hokkaido Kouseiren Kutchan Kousei Hospital for a left renal mass incidentally found by computed tomography. The tumor was 29 mm in diameter and showed ring-like calcification and heterogeneous enhancement by the contrast medium. The patient underwent left partial nephrectomy after the diagnosis of left renal cell carcinoma. Contrary to the radiographic finding, there was no palpable calcified lesion in the macroscopic specimen. Histopathologically, the tumor showed features of papillary renal cell carcinoma with massive psammoma bodies which might have been the cause for mimicking radiographic calcification.