title: FISH scoring on paraffin sections versus single-cell suspension for chromophobe renal carcinoma and renal oncocytoma.
abstract: BACKGROUND
  Sectioning of the nuclei on tissue sections may give an overestimate of monosomy, a feature diagnostic of chromophobe renal cell carcinoma versus renal oncocytoma. The aim of the study was to assess whether or not nuclear sectioning may distort the results obtained from interphase fluorescence in situ hybridization (FISH) comparing the data obtained from analysis of isolated nuclei derived from formalin-fixed, paraffin-embedded sections with histological sections from the adjacent sections from the same tumors.
  
  
  METHODS
  Five chromophobe renal cell carcinomas and five renal oncocytomas were recruited. Sections of 5 μm and 30 μm were cut for FISH to investigate chromosomes 1, 2, 6 10 and 17.
  
  
  RESULTS
  FISH of isolated nuclei from renal oncocytomas showed a mean increase of 3.0% for nuclei with two signals when compared to tissue sections. For chromosomes 2, 6, 10 and 17, isolated nuclei showed a mean increase of 4.9% of fluorescent signals over nuclei from tissue sections. FISH analysis of isolated nuclei from chromophobe renal cell carcinoma showed a similar counts.
  
  
  CONCLUSIONS
  When a tumor section exhibits a borderline percentage of nuclei with single signals around the cut-off level on tissue sections, the test should be repeated on isolated nuclei to confirm chromosomal loss, diagnostic of chromophobe renal carcinoma.
authors.affiliation: Department of Pathology and Diagnostic, University of Verona, P.le Ludovico Scuro 10, 37134 Verona, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Brunelli
authors.forename: Diego
authors.initials: D
authors.lastname: Segala
authors.forename: Brett
authors.initials: B
authors.lastname: Delahunt
authors.forename: Claudia
authors.initials: C
authors.lastname: Parolini
authors.forename: Samantha
authors.initials: S
authors.lastname: Bersani
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: John N
authors.initials: JN
authors.lastname: Eble
authors.forename: Marco
authors.initials: M
authors.lastname: Chilosi
authors.forename: Stefano
authors.initials: S
authors.lastname: Gobbo
authors.forename: Guido
authors.initials: G
authors.lastname: Martignoni
mesh_terms: D018249:Adenoma, Oxyphilic / Q000235:genetics* / Q000473:pathology*; D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000473:pathology*; D018929:Cell Culture Techniques / Q000379:methods*; D002467:Cell Nucleus / Q000473:pathology; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase; D007680:Kidney Neoplasms / Q000235:genetics* / Q000473:pathology*; D016612:Paraffin Embedding; D013535:Suspensions
chemical_list: D013535:Suspensions