Abstract: Background and purpose: We analyzed the distribution of metastatic sites and survival of lung cancer patients with metastases based on hospital registration to provide real-world data support for the treatment and survival management of lung cancer patients. Methods: A total of 1 490 lung cancer patients who developed metastasis during the follow-up in Fudan University Shanghai Cancer Center from 2008 to 2017 were enrolled in this study. Medical records review, telephone visits and death registry data linkage were applied in collecting endpoint data. The effects of age at diagnosis, gender and histological subtype on the distribution of metastases were studied. The Kaplan-Meier method was used to evaluate the overall survival (OS) rates of different metastatic sites. Results: The median follow-up time was 40.8 months. During the follow-up period, 937 cases died from all causes. 67.7% of patients only had single-site metastasis, while 32.3% of patients had multiple-site metastases. The common metastatic sites were bone (33.8%), brain (33.6%), lung (22.8%), liver (12.0%) and adrenal gland (3.7%). Female patients had more metastases to brain (37.8% vs 31.4%). Younger patients were more likely to develop multiple-site metastases, and small cell carcinomas patients had more brain metastases (47.2%) and liver metastases (20.9%). Lung metastasis featured relatively best survival (1-year OS rate: 78.3%, 3-year OS rate: 47.1%, 5-year OS rate: 29.5%), whereas liver metastasis had relatively the worst prognosis (1-year OS rate: 46.4%, 3-year OS rate: 15.2%, 5-year OS rate: 3.6%). Conclusion: The proportions of bone and brain metastases in lung cancer patients with metastasis are high. The distribution of metastatic sites is associated with gender, age at diagnosis and histological type. The prognosis of patient with different metastatic sites is different. Mechanisms or clinical treatment plans can be studied for different metastatic sites to improve the prognosis of late-stage lung cancer patients in future research.

Key words: Lung cancer, Metastatic site, Survival analysis, Hospital registration