COX-2 status is a significant factor to predict a postoperative survival as well as an efficacy of postoperative adjuvant therapy in non-small cell lung cancer

Abstract

9556 Background: Clinical significance of biomarkers in non-small cell lung cancer (NSCLC) remains unclear, and an exact and quantitative evaluation of biomarkers may be required to clarify the clinical significance. Methods: A total of 110 patients (pts) with completely resected p-stage I NSCLC were reviewed. RNAs were isolated from laser-captured tumor cells, and gene expression of VEGF, COX-2, MMP-2, MMP-9, EGFR, p27, TS, DPD, TP, and OPRT was quantitatively evaluated by a real-time RT-PCR assay. Results: COX-2 gene expression status was the only significant prognostic factor (Table), and a multivariate analysis confirmed that high COX-2 gene expression was an independent factor to predict a poor prognosis (p=0.005, RR=3.848 [95% CI, 1.500–9.874]). COX-2 gene expression status also predicted the efficacy of postoperative adjuvant chemotherapy using UFT (an oral 5-FU derivative); UFT administration was effective for low COX-2 gene-expression tumor (5-year survival rate, 93% for UFT-treated pts and 67% for surgery-alone pts; p=0.045), and was not effective for high COX-2 gene-expression tumor (5-year survival rate, 64% for UFT-treated pts and 62% for surgery-alone pts; p=0.677). COX-2 protein-expression status determined immunohistochemically was well correlated with COX-2 gene-expression status (p=0.001). However, COX-2 protein-expression status was not a significant prognostic factor nor a significant predictive factor of UFT administration. Conclusions: High COX-2 gene-expression in tumor cells was a significant factor to predict not only a poor prognosis but also an inefficacy of postoperative adjuvant chemotherapy for resected NSCLC. No significant financial relationships to disclose.