Ipsilateral retroperitoneal papillary renal cell carcinoma 27 years after simple nephrectomy for a renal abscess: A case report

Cases of severe inflammatory renal disease and renal cell carcinoma (RCC) that occur simultaneously in the same kidney have been occasionally reported. However, extrarenal RCC that does not originate from the native kidney has rarely been reported. To our knowledge, this is the first reported case of RCC developing in the ipsilateral retroperitoneal space after a simple nephrectomy (SN) for inflammatory renal disease. A 63-year-old woman was referred to our hospital following the incidental discovery of a left retroperitoneal mass without specific symptoms. Her medical history revealed a left SN 27 years ago due to a renal abscess. Magnetic resonance imaging of the abdomen revealed three oval masses in the left retroperitoneum. The masses were successfully excised, and subsequent pathology confirmed papillary RCC. After surgery, the patient remained disease-free for 11 years without adjuvant therapy. Clinicians should be vigilant of RCC in patients with retroperitoneal masses, especially after SN for inflammatory renal disease.