Value of TTF‑1 expression in non‑squamous non‑small‑cell lung cancer for assessing docetaxel monotherapy after chemotherapy failure

Abstract

Docetaxel is one of the standard second/third‑line treatments for non‑small‑cell lung cancer (NSCLC) following a failed response to prior cytotoxic chemotherapy. The predictive biomarker for the effectiveness of docetaxel therapy remains undetermined. However, thyroid transcription factor‑1 (TTF‑1) is known to be a good prognostic factor for a variety of chemotherapies. To investigate the association between TTF‑1 expression and docetaxel monotherapy outcome, 82 patients with non‑squamous NSCLC who received second/third‑line docetaxel monotherapy were retrospectively screened. All backgrounds were well‑balanced whether or not tumor TTF‑1 was expressed, and the present clinical outcomes were similar to those reported by previous clinical studies. A better clinical outcome was indicated in TTF‑1 positive compared with TTF‑1 negative patients, with disease control rates of 69% vs. 42%, respectively (P=0.03) and median overall survival of 393 days vs. 221.5 days, respectively (P<0.01). Furthermore, progression free survival tended to be longer in TTF‑1 positive compared with TTF‑1 negative patients (median, 100 days vs. 67 days; P=0.09). Multivariate analysis revealed that TTF‑1 positivity was a unique significant predictor for assessing overall survival after docetaxel monotherapy. TTF‑1 positivity may be useful for predicting survival outcome in patients who received docetaxel monotherapy after failure of prior chemotherapy.