A randomized, double-blind, comparison of radium-223 and placebo, in combination with abiraterone acetate and prednisolone, in castration-resistant metastatic prostate cancer: subgroup analysis of Japanese patients in the ERA 223 study

Japanese clinical practice guidelines for prostate cancer 2023

This fourth edition of the Japanese Clinical Practice Guidelines for Prostate Cancer 2023 is compiled. It was revised under the leadership of the Japanese Urological Association, with members selected from multiple academic societies and related organizations (Japan Radiological Society, Japanese Society for Radiation Oncology, the Department of EBM and guidelines, Japan Council for Quality Health Care (Minds), Japanese Society of Pathology, and the patient group (NPO Prostate Cancer Patients Association)), in accordance with the Minds Manual for Guideline Development (2020 ver. 3.0). The most important feature of this revision is the adoption of systematic reviews (SRs) in determining recommendations for 14 clinical questions (CQs). Qualitative SRs for these questions were conducted, and the final recommendations were made based on the results through the votes of 24 members of the guideline development group. Five algorithms based on these results were also created. Contents not covered by the SRs, which are considered textbook material, have been described in the general statement. In the general statement, a literature search for 14 areas was conducted; then, based on the general statement and CQs of the Japanese Clinical Practice Guidelines for Prostate Cancer 2016, the findings revealed after the 2016 guidelines were mainly described. This article provides an overview of these guidelines.

A Systematic Review of Patient Race, Ethnicity, Socioeconomic Status, and Educational Attainment in Prostate Cancer Treatment Randomised Trials-Is the Evidence Base Applicable to the General Patient Population?

Context

Prostate cancer (PC) disproportionately affects men of Black race, and lower educational and socioeconomic status. Guidelines are based on randomised controlled trials (RCTs); however, the representation of different races, educations, and socioeconomic backgrounds in these trials is unclear.

Objective

To assess reporting of equality, diversity, and inclusion characteristics (Equality, Diversity and Inclusion [EDI]) and differences in treatment effects between different races, and educational or socioeconomic status.

Evidence acquisition

We conducted a systematic review of CENTRAL, MEDLINE, and Embase in April 2020 examining RCTs investigating treatments for PC. Outcomes collected were race/ethnicity, educational attainment, and socioeconomic status. RCTs investigating PC treatment in any population or setting were included. Data extraction of characteristics was performed independently by pairs of reviewers and checked by a senior author. The Cochrane risk of bias tool assessed the quality of included papers.

Evidence synthesis

A total of 265 trials were included, and 138 of these were available as full-text articles. Fifty-four trials including 19 039 participants reported any EDI data. All 54 trials reported race, 11 reported ethnicity, three reported educational attainment, and one reported socioeconomic status. Patients of White race were the majority of the recruited population (82.6%), while the minority prevalence was as follows: Black 9.8% and Asian 5.7%. Three studies reported mortality outcomes depending on the participant's race. All three studies investigated different treatments, so a meta-analysis was not performed. No studies reported outcomes stratified by the educational or socioeconomic status of participants.

Conclusions

There is poor reporting of patient race, ethnicity, socioeconomic background, and educational attainment in RCTs for PC treatments between 2010 and 2020. Addressing this for future studies will help explain differences in the incidence of and mortality from PC and improve the generalisability of results.

Patient summary

In this study, we reviewed prostate cancer treatment trials to see whether these reported race, education, and socioeconomic backgrounds of their patient populations. We conclude that reporting of these characteristics is poor. This needs to be improved in future to improve outcomes for patients with prostate cancer of all ethnical, racial, and socioeconomic groups.

Administration of radium-223 and the prognosis in Japanese bone metastatic castration-resistant prostate cancer patients: A large database study

BACKGROUND

The ALSYMPCA trial revealed radium-223 (Ra-223) to be a life-prolonging agent for bone metastatic castration-resistant prostate cancer (CRPC). However, only 2.8% of enrolled patients in that clinical trial were Asian, and no Japanese patients were enrolled. Several retrospective studies have been published concerning Japanese bone metastatic CRPC patients receiving Ra-223. However, no study has yet reported the correlation between Ra-223 induction and the survival in Japanese bone metastatic CRPC patients. This study investigated the effect of Ra-223 as a life-prolonging agent in a large Japanese healthcare fee database.

METHODS

A total of around 410 000 prostate cancer patients were extracted from this database, and 25 934 were diagnosed with CRPC. In these patients, the age, date of the CRPC diagnosis, date of Ra-223 induction, and prognosis were analyzed.

RESULTS

A total of 1628 patients received Ra-223, and 6693 patients were diagnosed with bone metastasis CRPC, with the remaining 17 613 patients diagnosed with CRPC without bone metastasis. The patients who completed six courses of Ra-223 showed a significantly more favorable overall and cancer-specific survival than those who received ≤5 courses (p < 0.0001 and p < 0.0001, respectively). For time from CRPC diagnosis date to death, the Ra-223 induction group showed a significantly more favorable prognosis with regard to both the overall and cancer-specific survival than the bone metastatic CRPC patients without Ra-223 (p < 0.0001 and p < 0.0001, respectively).

CONCLUSIONS

Bone metastatic CRPC patients who received Ra-223 showed a significantly better prognosis than bone metastatic CPRC patients who did not receive Ra-223.

Updates in Management of Bone Metastatic Disease in Primary Solid Tumors with Systemic Therapies

PURPOSE OF REVIEW

The purpose of this review is to highlight novel and impactful discoveries in systemic treatment of bone metastatic disease in solid tumors published within the past 5 years.

RECENT FINDINGS

Major developments in systemic treatment of bone metastatic disease in solid tumors include evidence that decreasing frequency of dosing zoledronic acid in metastatic breast and prostate cancer maintains efficacy in preventing skeletal-related events while decreasing costs. The landmark findings on the use of Radium-223 to treat metastatic prostate cancer were reported in 2013. Recently, it has been found that not all systemic therapy combinations with Radium-223 are necessarily safe or effective unless bone-targeted therapy is also included in the regimen. More cost-effective dosing intervals of zoledronic acid and efficacy and safety nuances of combination radiopharmaceutical and chemotherapy treatment have been better delineated.

Prognosis and safety of radium‐223 with concurrent abiraterone acetate or enzalutamide use for metastatic castration‐resistant prostate cancer: Real‐world data of Japanese patients

Objectives

To evaluate the real‐world data on the efficacy and safety of a combination therapy with radium‐223 (Ra‐223) and second‐generation androgen‐receptor targeting agents (ARTAs), including abiraterone acetate (ABI) and enzalutamide (ENZ), among Japanese patients with bone metastatic castration‐resistant prostate cancer (CRPC).

Patients and methods

We retrospectively reviewed 79 patients with bone metastatic CRPC who were treated with Ra‐223. The number of patients with concurrent ARTA use was 24:17 receiving ABI and 7 receiving ENZ. We evaluated the overall survival (OS) according to ARTA use and compared the survival of patients treated with Ra‐223 with or without ARTA using multivariate analysis.

Results

The median survival in the entire cohort was 23.5 months. The patients receiving Ra‐223 combined with ARTA showed a tendency of better OS than patients treated with Ra‐223 alone, although no significant difference was observed (median OS, 26.5 vs 23.5 months; P = .115). A multivariate analysis showed that the extent of disease on bone scan (EOD) scores and pain at baseline were significant predictors of OS. The concurrent use of bone‐modifying agents (BMAs) was not significant for favorable OS (P = .050). However, the concurrent use of second‐generation ARTA was not a significant factor for OS. Regarding safety, a bone fracture occurred in only one (4.2%) of 24 patients treated with combined Ra‐223 and ARTA therapy.

Conclusion

Our real‐world data analysis suggested that Ra‐223 combined with a second‐generation ARTA is well tolerated in Japanese patients. The EOD score and pain at baseline are significant prognostic factors for OS, but the concurrent use of second‐generation ARTA has no influence on OS among men treated with Ra‐223. The concurrent use of BMA yields a marginally favorable OS.