title: Clinical investigation into the initial diagnosis and treatment of 539 patients with stage IV lung cancer.
abstract: OBJECTIVE
  The aim of the study was to analyze clinical data, including the types of pathologic classification, metastatic organs, treatment strategy, and prognosis of patients with stage IV lung cancer.
  
  
  METHODS
  A retrospective analysis of the clinical features of 539 patients with stage IV lung cancer who were initially diagnosed and treated in 2009 was conducted. There were 146 cases of single organ metastases and 393 cases of multiple organ metastases. The Kaplan-Meier method and multivariate Cox regression analysis were performed to analyze the influence of age, pathological classification, metastatic organs, and treatment strategy on overall survival.
  
  
  RESULTS
  The 1-, 2-, and 3-year survival rates were 64.2% (n=346), 19.7% (n=106), and 1.5% (n=8), respectively. Metastases to the liver and pleura predicted poor prognosis, although bone metastases predicted relatively good prognosis. The prognosis of single brain metastasis was relatively better than that of multiple brain metastases. Multi-factor analysis showed that the patient's age, different metastatic organs, the numbers of metastatic organs, and different treatment were independent risk factors for survival.
  
  
  CONCLUSIONS
  The prognosis for patients with stage IV lung cancer is poor. Patient's age, the type and number of metastatic organs, and method of treatment are the main factors affecting survival.
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Shao
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Fengxiang
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, People's Republic of China.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Li
keywords: carcinoma/lung; clinical analysis; diagnosis; prognosis; therapy