Type 2 and clear cell papillary renal cell carcinoma, and tubulocystic carcinoma: a unifying concept.

The clinical and pathological features of multiple different renal neoplasms arising in a setting of end-stage renal disease in a 72-year-old male are described. The kidney showed features of renal oncocytosis with multiple oncocytomas, hybrid tumours and chromophobe renal carcinoma. In addition, the kidney contained a type 2 papillary renal cell carcinoma, clear cell papillary and cystic renal cell carcinoma, and tubulocystic carcinoma. The occurrence of these three tumours in a setting of end-stage kidney disease is unique and suggests a common pathogenesis. Immunostaining of these tumours further suggests they are derived from similar stem cells which show immunophenotypic features of both the proximal and distal nephron.