136P - TTF1 Expression in Advanced Non-Small Cell Lung Cancer: Impact on Survival Outcome

Abstract

Aim: The prognostic role of TTF-1 expression in non-small cell lung cancer (NSCLC) was assessed in few studies with inconsistent results. The present study aims to evaluate the prognostic value of TTF1 expression in advanced non-squamous NSCLC. Methods: In this retrospective study, patients with stage IIIB-IV non-squamous NSCLC were included. Differences in progression free survival (PFS) and overall survival (OS) according to TTF1 expression status, type of 1st line chemotherapy (pemetrexed containing vs. others), EGFR status and other clinico-pathological parameters, were assessed using log rank test. Multivariate analyses using Cox proportional hazards models have been used to check for independent prognostic factors for PFS and OS. Results: One hundred and twenty patients with advanced non-squamous NSCLC were identified (stage IV: 100, stage IIIB: 20 and TTF1-positive: 100, TTF1-negative: 20). In univariate analysis, PFS was improved in patients with PS 0-2 (7.0 vs. 2.0 months, p= 0.002) and those who received pemetrexed-containing chemotherapy (9.2 vs. 5.8 months, p= 0.004). Meanwhile, PFS was improved in patients with TTF1-positive tumours; however, it did not reach statistical significance (6.8 months vs. 2.3 months, p= 0.17). OS was improved in female patients (23.0 vs. 8.7 months, p < 0.0001), those with pemetrexed-containing chemotherapy (17.0 vs. 11.0 months, p= 0.019), patients with PS 0-2 (14.4 vs. 2.0 months, p < 0.0001), TTF1-positive (12.8 vs. 5.8 months, p= 0.011) and EGFR- mutant patients (23.0 vs. 11.7 months, p = 0.006). In multivariate analysis, male gender (HR = 2.34, 95% CI= 1.11-4.94, p = 0.025) and non-pemetrexed containing therapy (HR = 2.24, 95% CI= 1.13- 4.45, p= 0.022) were independent predictors of worse PFS. Wild EGFR status (HR = 2.49, 95% CI = 1.19 -5.19, p = 0.015) and male gender (HR = 2.78, 95% CI = 1.30- 5.95, p = 0.008) were predictors of worse OS. TTF1 expression status was not an independent prognostic factor for OS (HR = 2.32, 95% CI= 0.53- 6.45, p= 0.10). Conclusions: TTF1 expression was not found to be a prognostic marker in advanced non-squamous NSCLC. Pemetrexed-containing therapy significantly improved PFS while OS was improved in EGFR mutant patients. Female patients had better PFS and OS. Disclosure: All authors have declared no conflicts of interest.