title: Percutaneous CT-guided microwave ablation as maintenance after first-line treatment for patients with advanced NSCLC.
abstract: BACKGROUND
  Systemic therapy is recommended for advanced non-small-cell lung cancer (NSCLC). However, conventional first-line treatment has generated a plateau in response rate of 25% to 35%. Few studies have shown patients benefit from microwave ablation (MWA) in combination with radiotherapy and chemotherapy. This study aims to evaluate safety and efficacy of percutaneous computed tomography-guided MWA as maintenance after first-line treatment for patients with advanced NSCLC.
  
  
  METHODS
  Patients with histologically verified NSCLC stage IIIB or IV between January 2010 and March 2014 were involved. After completion of first-line treatment with partial response or stable disease, 35 patients with 39 tumors underwent 39 MWA procedures. Complications, progression-free survival (PFS), overall survival (OS), and correlated predictors were analyzed.
  
  
  RESULTS
  During a median follow-up of 17.7 months and 10.8 months after initial MWA, local efficacy was 87.2%, median MWA-related local control time was 10.6 months, and tumor size was the only predictor (P=0.002). Median MWA-related PFS, MWA-related OS, PFS, and OS were 5.4, 10.6, 11.8 and 17.7 months, respectively. Local efficacy was significantly correlated with MWA-related PFS (P=0.003), MWA-related OS (P=0.000), and OS (P=0.001). There were no procedure-specific deaths. Total incidence of major complications was 12.8%, including pneumothorax resolved by closed pleural drainage and pneumonia controlled by antibiotics in a short time.
  
  
  CONCLUSIONS
  This study concluded two points, including: 1) patients benefited from MWA as maintenance both in local control and survival; 2) as maintenance MWA was superior to conventional maintenance therapy with improved survival and well-tolerated complications. Therefore, MWA was a safe and effective maintenance after first-line treatment in patients with advanced NSCLC.
authors.affiliation: Department of Oncology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, People's Republic of China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Ni
authors.affiliation: Department of Oncology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, People's Republic of China.
authors.forename: Jun-Qing
authors.initials: JQ
authors.lastname: Han
authors.affiliation: Department of Oncology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Ye
authors.affiliation: Department of Oncology, Shandong Provincial Hospital affiliated to Shandong University, Jinan, People's Republic of China.
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: Wei
keywords: CT-guided microwave ablation; non-small-cell lung cancer; overall survival; progression-free survival