title: Percutaneous core biopsy for renal masses: indications, accuracy and results.
abstract: OBJECTIVE
  We evaluated the results, accuracy and clinical incidence of our standard procedure of percutaneous biopsy for solid renal masses.
  
  
  METHODS
  From March 1999 to April 2005, 119 percutaneous core biopsies of renal masses were performed. Biopsies were proposed when there was no formal evidence for a carcinoma diagnosis on computerized tomography.
  
  
  RESULTS
  Benign lesions were diagnosed in 24 biopsies (20.1%), including oncocytoma in 13, angiomyolipoma in 5 and chronic pyelonephritis in 5. Malignancy was identified in 70 biopsies (58.8%), including 57 renal carcinomas (conventional renal cell in 41, papillary in 12 and chromophobe in 4), 4 transitional cell carcinomas, 8 metastases and 1 lymphoma. For 25 biopsies (21%) no accurate diagnosis was possible, including 12 that showed inflammatory tissue and 13 with normal or necrotic tissue. These inconclusive biopsies prompted repeat biopsy in 13 patients, in whom a total of 11 malignant lesions were diagnosed. A total of 64 nephrectomies were performed with a biopsy accuracy for histopathological tumor type and Fuhrman nuclear grade of 86% and 46%, respectively. A period of watchful waiting was proposed for 31 patients (34.2%) and no renal malignancies were found. Computerized tomography showed stabilization or disappearance of the initial renal mass.
  
  
  CONCLUSIONS
  Percutaneous renal tumor biopsies are safe, cost-effective and often conclusive for an acute histological diagnosis. This procedure could be decisive for choosing the optimal treatment, particularly to avoid nephrectomy for benign lesions. Biopsies should not be considered a routine procedure but they could be indicated when there is a lack of radiological evidence in elective patients.
authors: Department of Urology, Hôpital Foch, Suresnes, France. t.lebret@hopital-foch.org
authors: Thierry
authors: T
authors: Lebret
authors: Jean Eudes
authors: JE
authors: Poulain
authors: Vincent
authors: V
authors: Molinie
authors: Jean Marie
authors: JM
authors: Herve
authors: Yves
authors: Y
authors: Denoux
authors: Axel
authors: A
authors: Guth
authors: Antoine
authors: A
authors: Scherrer
authors: Henry
authors: H
authors: Botto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology*; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009403:Nephrostomy, Percutaneous; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed