Risk of cerebral metastases for postoperative locally advanced non-small-cell lung cancer.

Cerebral metastases are the main determining factor in the failure of locally advanced non-small-cell lung cancer (NSCLC) management. Our study assessed the risk factors of brain metastases in patients with postoperative, locally advanced NSCLC. Implications for PCI treatment are discussed. Two hundred twenty-three patients treated with surgical resection for stage III-N2 NSCLC were retrospective analyzed to elucidate risk factors for development of brain metastases, and to establish a mathematical model. Median survival time for this patient population was 29.5 months. Frequency of brain metastases in the entire patient population was 38.1% (85/223). Frequency of brain metastases in patients with single mediastinal lymph-node region with metastases at 1, 2, and 3 years was 5.6%, 14.0%, and 19.0%, respectively. The frequency of brain metastases in patients with multiple mediastinal lymph-node regions with metastases was 31.8%, 60.3%, 68.0%, respectively (P<0.001). The frequency of brain metastases among patients with mediastinal metastasis number less than 4, 4-6, and more than 6 was significantly different (P<0.001). There were also significant differences in brain metastases frequency between patients with complete versus incomplete resection (P=0.001), and patients with non-squmous versus squamous (P=0.029), and patients administered adjuvant chemotherapy versus none (P=0.032). A mathematical model to predict brain metastases risk was developed. It can aid in selection of patients with locally advanced NSCLC for PCI in clinical trails.