Purpose: We aimed to develop a nomogram able to predict treatment failure, skeletal events and overall survival (OS) in patients with castration-resistant prostate cancer with bone metastases (CRPC-BM) treated with Radium-223 dichloride (223Ra).
Patients and Methods: Patients from Castilla-La Mancha Spanish region was prospectively included in ChoPET-Rad multicenter study, from January 2015 to December 2022. Patients underwent baseline, interim, and end-of-treatment bone scintigraphy (BS) and 18F-Fluorocholine PET/CT (FCH PET/CT) scans, obtaining multiple imaging radiomics as well as clinical and biochemical variables during follow-up and studying their association with the previously defined end-points. Survival analysis was performed using Kaplan-Meier method and Cox regression. Multivariate logistic and Cox regression models were calculated, and these models were depicted by means of nomograms.
Results: Median progression-free survival (PFS) and OS for our population were 4 and 14 months (mo), respectively. The variables that showed the most robust independent significant association with therapeutic failure were baseline alkaline phosphatase (AP) levels (p=0.022) and the characteristics of BM on CT portion of PET/CT (p=0.017). In the case of OS, the significant variables were therapeutic failure (p=0.038), the number of lines received after 223Ra (p