Prognostic value of TTF-1 expression in patients with non-small cell lung cancer: A meta-analysis

Observational studies on the prognostic role of thyroid transcription factor 1 (TTF-1) in non-small-cell lung cancer (NSCLC) are controversial. To clarify the impact of TTF-1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios and their corresponding 95% confidence intervals were calculated in terms of overall survival. A total of 17 studies with 2235 patients were evaluable for this meta-analysis. The studies were categorized by histology, disease stage and patient race. Our results suggested that TTF-1 overexpression had a favorable impact on survival of patients with NSCLC, the HR (95% CI) was 0.49 (0.42 to 0.55) overall, 0.46 (0.38–0.54) in Asian patients, 0.52 (0.42–0.63) in non-Asian patients, 0.45 (0.38–0.52) in adenocarcinoma, 0.63 (0.39–0.86) in stage I NSCLC, and 0.43 (0.33–0.53) in stage IIIb–IV NSCLC. The data collected were not sufficient to determine the prognostic value of VEGF in patients with squamous cell lung carcinomas. But there was a high heterogeneity between the studies. TTF-1 overexpression indicates a favorable prognosis for patients with NSCLC, this effect appears also significant when the analysis is restricted in lung AC patients, stage I and stage IIIb–IV NSCLC.