[Xanthogranulomatous Pyelonephritis after Partial Nephrectomy Mimicking the Local Recurrence of Papillary Renal Cell Carcinoma].

A 55-year-old man underwent right partial nephrectomy and was diagnosed with papillary type 1 renal cell carcinoma (RCC), pT1a. The surgical margin was negative. Six months later, a follow-up computed tomography scan revealed that a mass appeared adjacent to the location of resection. There were no symptoms nor abnormal blood chemistry results at that time. The possibility of local recurrence of RCC could not be ruled out with by magnetic resonance imaging. Radical nephrectomy was performed for suspected rapid recurrence of RCC. Pathological diagnosis was xanthogranulomatous pyelonephritis but not malignancy.