Development and validation of a nomogram for prognosis of bone metastasis in patients with esophageal squamous cell carcinoma：A retrospective study in the SEER database and China cohort

Abstract

Purpose: Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor worldwide, and individuals with both ESCC and bone metastasis (BM) often face a challenging prognosis that is difficult to predict. 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) 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 2006to 2020. Clinicopathological features and significant prognostic factors for cancer-specific survival (CSS) were assessed through univariate and multivariate Cox proportional hazards regression analyses. Subsequently, a nomogram predicting CSS was developed utilizing the SEER database and externally validated using a 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, the results of multivariate regression analysis indicated that chemotherapy, radiotherapy, liver metastasis, brain metastasis, and sex were independent prognostic factors for ESCC with bone metastasis. The prognostic nomogram developed in the SEER cohort demonstrated areas under the ROC curve (AUCs) of 0.823, 0.796, and 0.800, respectively, for predicting 3-, 6-, and 12-month Cancer-Specific Survival (CSS).In the Chinese validation cohort, the nomogram exhibited acceptable discrimination ability (AUCs: 0.822, 0.763, and 0.727) and calibration. Conclusion: This study has constructed and validated a prognostic nomogram for predicting the CSS of ESCC patients with bone metastasis. The nomogram could potentially serve as a valuable tool for assessing survival and aiding clinicians in making individualized treatment decisions.