title: Ki-67 cell proliferation in familial and in esporadic unilateral retinoblastoma: case report.
abstract: OBJECTIVE
  Ki-67 is a nuclear protein that is expressed at all phases of the cell cycle except the resting phase. This study is a clinicopathologic observational case report that aims to report on the cell proliferation rates, as measured by the Ki-67 antigen, in two enucleated retinoblastoma eyes.
  
  
  METHODS
  One unilateral familial (mother with unilateral disease - patient 1) and one unilateral sporadic retinoblastoma (patient 2) patients were submitted to enucleation without previous treatment. The tumor cell proliferation rate was assessed by the Ki-67 antigen labeling index (stained cells / 100 cells) in five different fields of the tumor.
  
  
  RESULTS
  Patient 1 was 23 months old and the tumor was exophytic with associated neovascularization of the iris; patient 2 was 6 years old and the tumor was endophytic with coarse vitreous seeds. Both enucleated eyes presented optic nerve with free surgical margins. Positive Ki-67 cell index in patient 1 varied from 75 to 90 (MD +/- SD: 79.5 +/- 6.61) and in patient 2 from 38 to 60 (MD +/- SD: 46.6 +/- 8.2).
  
  
  CONCLUSIONS
  The familial retinoblastoma, besides the earlier age presentation, showed 45.8% more Ki-67 positive cells than the same stage sporadic one. This proliferation rate may explain the earlier presentation age of the tumor in the inherited disease.
authors.affiliation: Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brasil. mtbonanomi@uol.com.br
authors.forename: Maria Teresa Brizzi Chizzotti
authors.initials: MT
authors.lastname: Bonanomi
authors.forename: Fernando Betty
authors.initials: FB
authors.lastname: Cresta
authors.forename: Clayton César
authors.initials: CC
authors.lastname: Tokunaga
authors.forename: Ruth Miyuki
authors.initials: RM
authors.lastname: Santo
authors.forename: Otacilio de Oliveira
authors.initials: OO
authors.lastname: Maia
authors.forename: Walter Yukihiko
authors.initials: WY
authors.lastname: Takahashi
mesh_terms: D015415:Biomarkers / Q000032:analysis; D049109:Cell Proliferation; D002648:Child; D015353:Eye Enucleation; D005260:Female; D006801:Humans; D007223:Infant; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D010375:Pedigree; D019572:Retinal Neoplasms / Q000473:pathology* / Q000601:surgery; D012175:Retinoblastoma / Q000473:pathology* / Q000601:surgery; D016160:Retinoblastoma Protein / Q000032:analysis
chemical_list: D015415:Biomarkers; D019394:Ki-67 Antigen; D016160:Retinoblastoma Protein