Development and external validation of a novel prognostic nomogram for overall survival in prostate cancer patients with bone metastatic: a retrospective study of the SEER-based and a single Chinese center.

Abstract

Prostate cancer (PCa) patients with bone metastases (BM) often face a poor prognosis, a leading contributor to mortality within this group. This study aims to develop a novel prognostic nomogram to predict overall survival for them. We retrospectively analyzed PCa patients with BM from Surveillance, Epidemiology, and End Results (SEER) database and our hospital. Independent prognostic factors were identified using univariate and multivariate Cox regression analyses for the creation of a nomogram. Calibration curves and receiver operating characteristic (ROC) curves, along with the concordance index (C-index) and decision curve analysis (DCA), were employed to evaluate the performance of the constructed nomogram. A total of 12,344 PCa patients with BM, derived from 2010 to 2019 SEER database, were randomly allocated into a training cohort (n = 8640) and an internal validation cohort (n = 3704). Additionally, an external validation cohort (n = 126) from our hospital. The novel nomogram integrates multiple factors: age, race, histopathology, organ metastasis, chemotherapy, Gleason score, and prostate-specific antigen (PSA). C-index for the training, internal validation, and external validation cohorts were 0.770 (0.766-0.774), 0.756 (0.749-0.763), and 0.751 (0.745-0.757) respectively. Similarly, the area under the curve (AUC) for each cohort exhibited comparable results (training cohort-3-year: 0.682, 6-year: 0.775, 9-year: 0.824; internal validation cohort-3-year: 0.681, 6-year: 0.750, 9-year: 0.806; external validation cohort-2-year: 0.667, 3-year: 0.744, 4-year: 0.800), indicating that the nomogram possesses robust discriminative ability. Calibration curve and DCA curve further proved the reliability and accuracy of the prognostic nomogram. This study determined the independent risk factors for prostate cancer (PCa) patients with bone metastasis (BM) and subsequently developed a robust prognostic nomogram to predict overall survival (OS). This tool can serve to guide precise clinical treatment strategies for these patients.