TTF1 negative in non small cell lung cancer adenocarcinoma: A prognostic factor.

Abstract

e20004 Background: Patients with thyroid transcription factor 1 (TTF1) negative lung adenocarcinoma (ADC) have been reported to have a worse prognosis and to lack epidermal growth factor receptor (EGFR) mutations. This study describes a series of sample tumors from patients with clinically confirmed lung cancer. Methods: In all lung cancer patients diagnosed in the University Hospital of Lleida from January 2011 to December 2016, a real world data study of TTF1-negative ADC was performed, using TTF1 clone 8G7G3/1(DAKO). Each patient’s clinical history, pathology specimens and molecular results were noted. Two hundred and thirty one patients with TTF1 positive lung ADC formed the control group. Results: Twenty seven (27) patients were identified with ADC TTF1 negative (74% males). The media age was 66 years. The smoking history was as follows: 55,5% former, 29,6% ex smokers and 14,8% never smokers. The clinical stages were as follows: stage I or II (n = 3 [11%]), stage III (n = 4 [14,8%]) and stage IV (n = 20 [74%]). Patients’ mean survival was 7,6 vs 24,4 months in ADC TTF1 negative patients (P = 0,00001). Three hundred and thirty four (334) patients with ADC were found, TTF1 results were available in 258 (77,2%) cases, of them twenty-seven cases (10,4%) had TTF1 negative; when they were compared with the control group, TTF1 negative patients had overall shorter survival (P = 0,00001), regardless of whether patients were treated with radical or palliative intent: 34,4 vs 10, months P = 0,00001 (radical treatment) and 14,6 vs 6,7 months P = 0,007 (palliative intent). EGFR mutations were less frequent (P = 0,046) in TTF-negative tumors 5,5% vs 25,3%. Conclusions: Patients with TTF1 negative NSCLC ADC, have worse overall survival regardless of treatment intention and a lower frequency of EGFR mutations.