The prognostic analysis of different metastatic patterns in extensive-stage small-cell lung cancer patients: a large population-based study.

Aim: To analyze the metastasis patterns and prognosis differences for extensive-stage small-cell lung cancer patients. Methods: Log-rank tests were used to calculate and compare survival estimates. Cox regression analyses were used to evaluate the prognosis factors. Results: The liver was the most common metastatic site, and lung was the least common. In two metastatic sites, liver and bone metastases were the most common combination of sites. An isolated liver metastasis had the worst overall survival (OS) and cancer-specific survival (CSS) among metastatic sites (both p<0.001). Liver and lung metastases were associated with worse CSS (p<0.039) and OS (p<0.015). However, for patients with three metastatic sites showed no statistical differences in their CSS and OS (all, p>0.05). Conclusion: Extensive-stage small-cell lung cancer patients with metastasis to the liver alone or in combination with other organs appear to have worse outcomes.