TTF-1 Expression Predicts the Merit of Additional Antiangiogenic Treatment in Non-squamous Non-small Cell Lung Cancer

概要

Addition of antiangiogenic agent, bevacizumab, to platinum drug combined therapy is one of the standard chemotherapeutic regimens for advanced non-squamous non-small cell lung cancer (NS-NSCLC). However, a predictive marker of the effectiveness of bevacizumab is not established. Recently, thyroid transcription factor 1 (TTF-1), which is used as a diagnostic marker for lung adenocarcinoma in clinical practice, was shown to reprogram angiogenic activities through the proangiogenic factor. To investigate whether TTF-1 expression predicts a beneficial response of non-squamous non-small-cell lung cancer (NS-NSCLC) patients to bevacizumab, we retrospectively screened 118 advanced NS-NSCLC patients who were treated with pemetrexed plus platinum derivatives alone (Bev(-)) or with bevacizumab (Bev(+)). We investigated the relationship between expression of TTF-1 and treatment outcomes. Among the 92 TTF-1-positive patients, clinical outcomes in the Bev(+) group were significantly better than those in the Bev(-) group (response rate, 51.4% vs. 27.3%, p=0.027; median progression-free survival, 216 days vs. 137 days, p=0.012). Overall survival in the Bev(+) group tended to be longer than that in the Bev(-) group. However, the addition of bevacizumab to the standard treatment of 26 TTF-1-negative patients offered no clinical benefit. TTF-1 expression may serve as a predictive marker to identify patients who may benefit from the addition of bevacizumab to platinum doublet therapy.