Serum osteopontin levels are highly prognostic for survival in advanced non-small cell lung cancer: Results from JMTO LC 0004

BACKGROUND: The Japan-Multinational Trial Organization (JMTO) lung cancer (LC) 0003 was a prospective randomized phase III trial investigating advanced non-small cell lung cancer comparing paclitaxel (P) plus carboplatin (C) versus vinorelbine (V), gemcitabine (G) followed by docetaxel (D). This trial was conducted with Southwest Oncology Group (SWOG) 0003 using a common arm of PC. An analysis of SWOG 0003 samples showed that low osteopontin (OPN) plasma levels were highly prognostic for a better outcome. We performed an independent investigation to validate these results using samples from Japanese patients enrolled in the JMTO LC 0004, a correlative study associated with JMTO LC 0003. METHODS: A total of 20 ml of blood was collected before treatment from patients enrolled in JMTO LC 0003. Serum concentrations of OPN and basic fibroblast growth factor (bFGF) were measured by enzyme-linked immunosorbent assay. Effects of OPN and bFGF levels on tumor response, progression-free survival (PFS), and overall survival (OS) were examined. RESULTS: Seventy-one samples were obtained, including 32 specimens from the PC arm and 39 from the VGD arm. There were no significant relationships between either OPN or bFGF levels with patient characteristics. In an analysis of clinical outcome, low OPN levels correlated with better OS and progression-free survival (hazard ratio [HR] = 0.57; 95% confidence interval [CI], 0.33-0.97; p = 0.037, HR = 0.42; 95% CI, 0.25-0.70; p = 0.001, respectively) and high bFGF levels correlated with better OS (HR = 0.53; 95% CI, 0.31-0.90; p = 0.018). CONCLUSION: Consistent with the findings from SWOG 0003, low OPN serum levels were significantly associated with a favorable prognosis in the JMTO LC 0004. Additionally, high bFGF levels were associated with improved survival.