Renal oncocytoma: multifocality, bilateralism, metachronous tumor development and coexistent renal cell carcinoma

J Urol. 1999 Jul;162(1):40-2. doi: 10.1097/00005392-199907000-00010.


Purpose: We analyzed a large series of cases of renal oncocytoma to define the incidence of coexistent renal cell carcinoma, multifocality, bilateralism and metachronous tumor development.

Materials and methods: Between 1980 and 1997, 100 men and 38 women with a mean age of 68 years with oncocytoma, were treated surgically at our institution. We analyzed tumor characteristics and reviewed specimens for coexistent renal cell carcinoma.

Results: Tumors were discovered incidentally in 58% of the cases. Specimens were obtained from 84 radical and 70 partial nephrectomies. Tumor size ranged from 0.3 to 14.5 cm. (median 3.2). Oncocytoma was unilateral in 131 cases (95%) and bilateral in 7 (5%), while there were multiple oncocytomas in 8 (6%). Mean followup was 41 months (range 0 to 200). The disease specific survival rate was 100% and no patient had metastasis. In 6 patients (4%) metachronous oncocytoma developed during followup. No patient had locally recurrent oncocytoma after partial nephrectomy for a solitary renal oncocytoma. Renal cell carcinoma and oncocytoma were found in 14 patients (10%), including unilateral synchronous disease in 9 and bilateral synchronous disease in 5.

Conclusions: Our data support the benign nature of renal oncocytoma. Multifocality, bilateralism and metachronous tumor develop in approximately 4 to 6% of all cases. Renal cell carcinoma coexisted in 10% of oncocytoma cases.

MeSH terms

  • Adenoma, Oxyphilic / epidemiology*
  • Adenoma, Oxyphilic / pathology
  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Renal Cell / epidemiology*
  • Carcinoma, Renal Cell / pathology
  • Female
  • Humans
  • Incidence
  • Kidney Neoplasms / epidemiology*
  • Kidney Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasms, Multiple Primary / epidemiology*
  • Neoplasms, Multiple Primary / pathology