Metastasis patterns and prognosis in young breast cancer patients: A SEER database analysis
Weifang Zhang, Shang Wu, Jinzhao Liu, Xiangmei Zhang, Xindi Ma, Chao Yang, Miao Cao, Shuo Zhang, Yunjiang Liu
Abstract
Background: There are few studies on young patients with metastatic breast cancer (MBC). This study aims to explore the metastasis pattern and prognosis of young patients with MBC. Methods: test was used to compare clinicopathological characteristics. Survival differences were compared by Kaplan-Meier analysis. Cox regression models were used to determine the prognostic factors affecting survival. Propensity score matching (PSM) was performed to balance the effects of baseline clinicopathological differences. Results: Finally, 494 patients (7.8%) who are ≤40 years old and 5,842 patients (92.2%) who are >40 years old were included. In the younger group, the proportion of liver metastasis was significantly higher than that in the older group; the proportion of lung metastasis was significantly lower than that of the older group. Kaplan-Meier analysis showed that the younger group had the best prognosis and the older group had the worst. Youth is an independent protective factor for overall survival (OS). In the younger group, liver metastasis had the best prognosis among all metastatic sites, and the HER2-enriched subtype had the best prognosis among all subtypes. Conclusions: The disease in young MBC patients is more aggressive but has a better prognosis, especially in liver metastases and the HER2-enriched subtypes.