Abstract
PURPOSE: Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor worldwide, and individuals with ESCC and bone metastasis (BM) often face a challenging prognosis. Our objective was to identify the risk and prognostic factors associated with BM in patients with ESCC and develop a nomogram for predicting Cancer-Specific Survival (CSS) which following the occurrence of BM. METHODS: We conducted a retrospective analysis of data pertaining to ESCC patients with BM registered in the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015, as well as those treated at a Chinese institution from 2006 to 2020. Significant prognostic factors for CSS were assessed through univariate and multivariate Cox regression analyses. Subsequently, a nomogram was developed utilizing the SEER database and externally validated using real-world evidence from a Chinese cohort. RESULTS: A total of 266 patients from the SEER database and 168 patients from the Chinese cohort were included in the analysis. In the SEER cohort, multivariate analysis indicated that chemotherapy, radiotherapy, liver metastasis, brain metastasis, and sex were independent prognostic factors for ESCC with BM. The prognostic nomogram demonstrated areas under the ROC curve (AUCs) of 0.823, 0.796, and 0.800, respectively, for predicting 3-, 6-, and 12-month CSS. In the Chinese validation cohort, the nomogram exhibited acceptable discrimination (AUCs: 0.822, 0.763, and 0.727) and calibration ability. CONCLUSION: The study developed a prognostic nomogram to predict CSS in ESCC patients with BM, which can help clinicians assess survival and make individualized treatment decisions.