Clinical outcomes, management, and treatment patterns in patients with metastatic castration‐resistant prostate cancer treated with radium‐223 in community compared to academic settings

Abstract

Background:The most common site of disease in metastatic castration-resistant prostate cancer (mCRPC) is the bone. The ALSYMPCA study demonstrated that radium-223 significantly improved overall survival (OS) in mCRPC patients with symptomatic bone metastases and without visceral metastases. However, administration requires a multidisciplinary approach and an infrastructure that supports coordination of care, which may differ by practice site. We aimed to evaluate practice patterns and treatment outcomes in patients with mCRPC treated at a community practice (CP) compared with those treated at an academic center (AC). Methods: This retrospective review included 200 adult mCRPC patients receiving radium-223 between January 2014 and June 2017. The primary endpoint, OS, was estimated from the date of radium-223 initiation. Secondary outcomes included a comparison of baseline characteristics, reasons for initiation and discontinuation of radium-223, and treatment sequencing. A subset analysis of OS based on the number of radium-223 doses and on sequencing of radium-223 either before or after chemotherapy was also conducted.Results: Most patients were treated at a CP (57%). Patients treated at CP sites were significantly older (74.9 vs. 71.9 years; p = .031) and had more comorbidities (Klabunde score 1.1 vs. 0.7; p = .020) than those in an AC but initiated treatment within a shorter period of time from diagnosis of mCRPC (1.3 vs. 1.9 years; p < .001) and received a greater mean number of radium-223 doses (5.4 vs. 4.8; p = .001). There were no observed differences in OS between CPs versus ACs (21.6 vs. 20.7 months; p = .306).Overall, patients who received 5-6 doses versus 1-4 doses of radium-223 had a longer median OS (23.3 vs. 6.4 months; p < .001). The most common reason for discontinuation in patients who did not complete treatment was disease progression. Overall, 43% of patients received radium-223 monotherapy and 57% concurrently with other agents.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Real‐world safety and effectiveness of radium‐223 in patients with metastatic castration‐resistant prostate cancer: Interim analyses of the prospective, observational RAPIT study

“…RAPIT is the largest real-world study of 223 Ra in Taiwanese patients with mCRPC (previous real-world studies in Taiwan were all <50 patients [18][19][20] ). In RAPIT, the median OS with 223 Ra was generally consistent with that seen in previous clinical, 13,21,22 prospective, 23 and retrospective 18,[24][25][26][27] studies in Asian 18,21,22 and Western 13,[23][24][25][26][27] populations. Furthermore, tALP and PSA responses were similar to those reported in a phase 3 study in Asian patients, 21 with tALP responses also being comparable with ALSYMPCA findings.…”

Real-world effectiveness, long-term safety and treatment pathway integration of radium-223 therapy in patients with metastatic castration-resistant prostate cancer

“…OS benefits were more notable ( P < 0.01 where reported) in patients who completed 5–6 vs. fewer cycles of 223 Ra ( 28 – 34 ) ( Figure 1A ). Factors associated with completion of 5–6 cycles in some studies included certain patient/disease characteristics ( 29 , 33 , 35 , 36 ) [e.g., lower PSA or alkaline phosphatase (ALP) ( 35 ) and absolute neutrophil count at least lower limit of normal ( 36 )] and earlier 223 Ra use ( 29 ) ( Figure 1B ). Indeed, there was a higher likelihood of completing all 6 cycles of 223 Ra when it was given prior- vs. post-chemotherapy ( P < 0.001) ( 32 ).…”

Radium-223 Utilization Patterns and Outcomes in Clinical Practice

“…Several studies have been published examining real-world outcomes using radium-223; however, the majority are comprised of smaller cohorts from a limited number of facilities. 6–12 We described the use of radium-223 in a large and multiracial population of men in the entire Veterans Affairs (VA) Healthcare System. We identified common treatment patterns associated with radium-223 and compared differences in OS and time to first skeletal-related event (SRE) between patients who received different treatment patterns.…”