Prognostic significance of cyclooxygenase-2 overexpression in glottic cancer.
OBJECTIVE
Cyclooxygenase-2 (COX-2) overexpression has been associated with a poor prognosis in many cancers. However, the role of COX-2 overexpression in head and neck cancers remains undetermined. The objective of this study was to evaluate whether COX-2 is a prognostic factor in glottic cancer.


METHODS
This study was part of a phase III placebo-controlled randomized trial evaluating the efficacy of alpha-tocopherol in reducing second primary cancers (SPC) in head and neck cancer patients. Immunohistochemical analyses were conducted on pretreatment biopsies of 301 patients with early-stage glottic cancer treated by radiotherapy. The median value of 50% of positive tumor cells was the cutoff point used to define COX-2 overexpression. Outcomes considered in the statistical analysis were recurrence, SPC, and death. The Cox proportional hazards model was used to estimate the hazard ratios (HR) and their 95% confidence intervals (95% CI).


RESULTS
The HR associated with COX-2 overexpression was 0.94 (95% CI, 0.55-1.62) for recurrence. The HR associated with SPC was 2.63 (95% CI, 1.32-5.23) for the first 3.5 years of follow-up and 0.55 (95% CI, 0.22-1.32) for the following 3.5 years. The HR associated with COX-2 overexpression was 1.57 (95% CI, 1.01-2.45) for overall mortality.


CONCLUSIONS
COX-2 overexpression in glottic cancer was associated with increased overall mortality and an increased risk of SPC during the early follow-up period. Future studies are needed to explain observed effects on SPC. COX-2 expression may prove helpful in defining an individual patient's prognosis.
Sackett
Melanie K
MK
Pathology Department, Centre Hospitalier Universitaire de Québec and Université Laval, Quebec, Canada.
Bairati
Isabelle
I
Meyer
François
F
Jobin
Edith
E
Lussier
Sébastien
S
Fortin
André
A
Gélinas
Michel
M
Nabid
Abdenour
A
Brochet
François
F
Têtu
Bernard
B
D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D004311:Double-Blind Method; D005260:Female; D005931:Glottis / Q000378:metabolism / Q000473:pathology*; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D007822:Laryngeal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000401:mortality / Q000517:prevention & control; D010919:Placebos; D011379:Prognosis; D014815:Vitamins / Q000627:therapeutic use; D024502:alpha-Tocopherol / Q000627:therapeutic use
D014408:Biomarkers, Tumor; D010919:Placebos; D014815:Vitamins; D051546:Cyclooxygenase 2; D024502:alpha-Tocopherol