Prognostic Value of the BIO-Ra Score in Metastatic Castration-Resistant Prostate Cancer Patients Treated with Radium-223 after the European Medicines Agency Restricted Use: Secondary Investigations of the Multicentric BIO-Ra Study
Matteo Bauckneht, Sara Elena Rebuzzi, Marta Ponzano, Roberto Borea, Alessio Signori, Viviana Frantellizzi, Elisa Lodi Rizzini, Manlio Mascia, Valentina Lavelli, Alberto Miceli, Maria Silvia De Feo, A Pisani, Susanna Nuvoli, Vincenzo Tripoli, A.G. Morganti, Paolo Mammucci, S Caponnetto, Guglielmo Mantica, Angelo Domenico Di Nicola, Carlo Villano, Luca Cindolo, Silvia Morbelli, Gianmario Sambuceti, Stefano Fanti, Renato Costa, Angela Spanu, Giuseppe Rubini, Fabio Monari, Giuseppe De Vincentis, Giuseppe Fornarini
Abstract
The multicentric retrospective BIO-Ra study combined inflammatory indices from peripheral blood and clinical factors in a composite prognostic score for metastatic castration-resistant prostate cancer patients receiving Radium-223 (Ra-223). In the present study, we evaluated (i) the prognostic power of the BIO-Ra score in the framework of the restricted use of Ra-223 promoted by the European Medicines Agency in 2018; (ii) the treatment completion prediction of the BIO-Ra score. Four hundred ninety-four patients from the BIO-Ra cohort were divided into three risk classes according to the BIO-Ra score to predict the treatment completion rate (p < 0.001 among all the three groups). Patients receiving Ra-223 after restriction (89/494) were at later stages of the disease compared with the pre-restriction cohort (405/494), as a higher percentage of BIO-Ra high-risk classes (46.1% vs. 34.6%) and lower median Overall survival (12.4 vs. 23.7 months, p < 0.001) was observed. Despite this clinically relevant difference, BIO-Ra classes still predicted divergent treatment completion rates in the post-restriction subgroup (72%, 52.2%, and 46.3% of patients belonging to low-, intermediate-, and high-risk classes, respectively). Although the restricted use has increased patients at higher risk with unfavourable outcome after Ra-223 treatment, the BIO-Ra score maintains its prognostic value.