Ki-67 cell proliferation in familial and in esporadic unilateral retinoblastoma: case report.
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.
Bonanomi
Maria Teresa Brizzi Chizzotti
MT
Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, Brasil. mtbonanomi@uol.com.br
Cresta
Fernando Betty
FB
Tokunaga
Clayton César
CC
Santo
Ruth Miyuki
RM
Maia
Otacilio de Oliveira
OO
Takahashi
Walter Yukihiko
WY
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
D015415:Biomarkers; D019394:Ki-67 Antigen; D016160:Retinoblastoma Protein