Positive thyroid transcription factor I staining strongly correlates with survival of patients with adenocarcinoma of the lung

This study investigated the relation between positive thyroid transcription factor 1 (TTF1) staining and survival of patients affected by primary adenocarcinoma (ADC) of the lung. Pathological tissue from consecutive ADC patients was collected from 2002 to 2004. The anti-TTF1 antibody (8G7G3/1, dilution of 1/200) was used. Thyroid transcription factor 1 staining was assessed for each tumour as positive or negative. Probability of survival was estimated by Kaplan-Meier and difference tested by log-rank test. A Cox's regression multivariate analysis was carried out. In all, 106 patients were studied (66% male, 69% PS0-1, 83% with stage III or IV). Tumours expressed positive TTF1 staining in 66% of cases. Multivariate analysis demonstrated an independent lower risk of death for patients whose tumour expresses positive TTF1 staining (HR = 0.51, 95% CI 0.30-0.85; P = 0.01) and higher grade of differentiation (HR = 0.40, 95% CI 0.24-0.68; P = 0.001). In conclusion, positive TTF1 staining strongly and independently correlates with survival of patients with primary ADC of the lung.