title: Histopathologic findings of small renal tumor biopsies performed immediately after cryoablation therapy: a retrospective study of 50 cases.
abstract: OBJECTIVE
  To evaluate the histopathology of small renal tumor biopsies following cryoablation.
  
  
  METHODS
  We retrospectively evaluated small renal tumor biopsy specimens after cryoablation treatment for renal cell carcinoma and determined the ability to differentiate tumor types, effect on nuclear grading, immunohistochemical staining, and if the number of freeze cycles affected interpretation.
  
  
  RESULTS
  Of the biopsy specimens, 66% were diagnostic of tumor and 34% showed normal renal parenchyma. Tumor subtype was determined in 91% of diagnostic cases. Nuclear grading was affected due to freeze effect, complicating the assessment of chromatin pattern and nucleolar details at low magnification. In particular, the distinction between Fuhrman nuclear grades I and II was compromised; these were designated as low nuclear grade. Immunohistochemical staining was retained similar to untreated tumors. Tumor subtyping was not affected after one or two freeze cycles.
  
  
  CONCLUSIONS
  Biopsies performed immediately after cryoablation can be used to render an optimal histologic diagnosis.
authors.affiliation: Denver Health Medical Center, 777 Bannock St MC0206, Denver, CO 80204; Fernando. kim@dhha.org.
authors.forename: Shalini
authors.initials: S
authors.lastname: Tayal
authors.forename: Fernando J
authors.initials: FJ
authors.lastname: Kim
authors.forename: David
authors.initials: D
authors.lastname: Sehrt
authors.forename: Roberto
authors.initials: R
authors.lastname: Miano
authors.forename: Alexandre
authors.initials: A
authors.lastname: Pompeo
authors.forename: Wilson
authors.initials: W
authors.lastname: Molina
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002292:Carcinoma, Renal Cell / Q000473:pathology* / Q000601:surgery; D003452:Cryosurgery; D005615:Freezing; D006801:Humans; D007150:Immunohistochemistry; D007668:Kidney / Q000473:pathology; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D012189:Retrospective Studies
keywords: Biopsies; Histopathologic findings; Post-cryoablation; Renal cell carcinoma; Small renal tumors