The expression of cyclooxygenase 2 in retinoblastoma: primary enucleated eyes and enucleation after conservative treatment.
OBJECTIVE
To provide insight into the relationship between cyclooxygenase-2 (COX-2) expression and histopathologic features of retinoblastoma specimens treated either by primary or secondary enucleation.


METHODS
Laboratory investigation.


METHODS
Twenty-five retinoblastoma specimens received between 1994 and 2003 were retrieved for this study from the Ocular Pathology Registry, Federal University of São Paulo, Brazil and the Henry C. Witelson Ocular Pathology Laboratory and Registry, McGill University, Montreal, Canada. The specimens retrieved were divided into two groups: Group I, enucleation was performed as a form of primary treatment (n = 15) and Group II, enucleation after failure of conservative treatment (n = 10). Patient information and formalin-fixed, paraffin-embedded specimens were obtained. New sections of these blocks were used for hematoxylin and eosin stain and for immunoassay using a monoclonal mouse anti-COX-2 antibody. Two independent ophthalmic pathologists reviewed all of the microslides.


RESULTS
Twenty-three specimens (92%) presented a high expression of COX-2 (15 in Group I; eight in Group II) and there was no statistical difference in COX-2 expression between the two groups (P = .07). However, all specimens expressed COX-2 to a different degree. The areas of tumor invasion were positive for COX-2 in 87.5% of the two groups.


CONCLUSIONS
Most retinoblastoma specimens revealed a high COX-2 expression. Future studies will be necessary to correlate the high expression of COX-2 in retinoblastoma and a possible applicability of anti-COX-2 medications in the treatment of these tumors.
Souza Filho
João Pessoa
JP
Henry C Witelson Ocular Pathology Laboratory, McGill University, Montreal, QC, Canada. jpessoafilho@hotmail.com
Martins
Maria C
MC
Correa
Zelia Maria S
ZM
Odashiro
Alexandre N
AN
Antecka
Emilia
E
Coutinho
Anamaria B
AB
Macedo
Carla R
CR
Vianna
Raul N G
RN
Burnier
Miguel N
MN
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D015353:Eye Enucleation; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D008297:Male; D012042:Registries; D019572:Retinal Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D012175:Retinoblastoma / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology / Q000601:surgery
D051546:Cyclooxygenase 2