title: Computed tomography-guided renal tumor biopsies: tumor imaging features affecting sample adequacy.
abstract: OBJECTIVE
  The aim of this study was to derive a model that predicts when a computed tomography (CT)-guided renal tumor biopsy will be diagnostic based on the tumor's unenhanced imaging characteristics.
  
  
  METHODS
  The CT images used to guide percutaneous biopsy and the pathology reports of 276 consecutive patients undergoing renal tumor biopsy were retrospectively reviewed. The effect of tumor size, growth pattern, location, and CT attenuation on the diagnostic biopsy rate was assessed using univariate and multivariate techniques. A model was derived using logistic regression, and its discrimination was evaluated using receiver operator characteristic curves.
  
  
  RESULTS
  The diagnostic rate for all masses was 76.8% (212/276). Univariate and multivariate analyses revealed that increasing size and solid tumor attenuation were associated with diagnostic biopsies. The model demonstrates a discrimination of 0.71.
  
  
  CONCLUSIONS
  The likelihood of a diagnostic biopsy of a solid tumor smaller than 1 cm and of any cystic tumor is significantly less than for larger solid renal tumors. The predictive model demonstrates moderate discrimination.
authors.affiliation: Department of Radiology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157-1088, USA. idavis@wfubmc.edu
authors.forename: Ivan C
authors.initials: IC
authors.lastname: Davis
authors.forename: Marta E
authors.initials: ME
authors.lastname: Heilbrun
authors.forename: Kaan
authors.initials: K
authors.lastname: Tangtiang
authors.forename: David D
authors.initials: DD
authors.lastname: Childs
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Zagoria
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000473:pathology*; D016009:Chi-Square Distribution; D003287:Contrast Media; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D015641:Radiography, Interventional / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media