A Risk Stratification Model for Predicting Survival in Breast Cancer Patients With Lung Metastasis: A Study of the SEER Database and A Chinese Cohort

Background: Distant metastases are the leading cause of death among breast cancer (BC) patients, and lung is the second preferential colonized sits. However, there has been no prognostic evaluation of BC patients with lung metastases so far. This research aimed to predict the overall survival (OS) and breast cancer-specific survival (BCSS) for BC patients with lung metastases and stratify them into different risk groups. Result: A total of 3888 patients from the SEER database were eligible for the subsequent analyses, with the training cohort of 1944 patients and the validation cohort I of 1944 patients. In addition, 374 patients from the Chinese XXX database were assigned as the validation II. Race, age, grade, subtype, number of metastatic sites, surgery, and chemotherapy were identified as determinant prognostic variables and integrated to construct the nomogram. Ultimately, a risk stratification model was established, and all patients were classified as three risk groups. Conclusion: We constructed prognostic prediction and risk stratification models for BC patients with lung metastases and validated it in both the SEER cohort and the Chinese cohort; these could assist clinicians in risk prediction, prognosis evaluation, and decision making on an individualized basis.