Ethnic Pharmacogenomic Differences in the Management of Asian Patients with Metastatic Prostate Cancer

A territory-wide real-world efficacy and toxicity analysis of abiraterone acetate versus docetaxel in 574 Asian patients with metastatic hormone-sensitive prostate cancer

INTRODUCTION

Abiraterone acetate (ABI) or docetaxel (DOC), in addition to androgen-deprivation therapy (ADT), are current treatment options for metastatic hormone-sensitive prostate cancer (mHSPC). No randomized head-to-head trial has compared these 2 mHSPC treatments, and real-world data regarding their outcomes in Asian patients are lacking.

PATIENTS AND METHODS

The medical records of mHSPC patients who began upfront ABI or DOC treatment in addition to ADT at seven public oncology centers in Hong Kong between 2015 and 2021 were reviewed. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), prostate-specific antigen (PSA) response, and toxicities. Kaplan-Meier and multivariate Cox regression analyses were performed.

RESULTS

A total of 574 patients were included, of whom 419 received DOC and 155 received ABI. The median follow-up duration was 22.4 (DOC group: 23.8; ABI group: 17.3) months. The ABI group demonstrated significantly better PFS than the DOC group (not reached vs. 15.1 months: hazard ratio = 0.37; 95% confidence interval = 0.28-0.50; P < .001). No significant OS difference was observed (P = .58). Failure to achieve a ≥ 90% decline in PSA level at 3 months and failure to achieve an undetectable PSA nadir were each associated with unfavorable PFS and OS. Patients who received DOC had a higher rate of febrile neutropenia, whereas those who received ABI had higher rates of grade ≥ 3 hypokalemia and elevated alanine transaminase. Treatment discontinuation due to toxicities was more common in the DOC (3.6%) than the ABI (0.6%) group.

CONCLUSION

In Asian mHSPC patients, upfront ABI + ADT was associated with better PFS than DOC + ADT, with no significant OS difference. PSA kinetics may help stratify the prognosis for treatment intensification. Toxicity profiles were different, with a higher rate of toxicity-related treatment discontinuation in the DOC group.

Outcomes and prognostic predictors of Lu-177 PSMA radioligand therapy in metastatic castration-resistant prostate cancer (Asian Population Study)

AIM

Lutetium-177 (Lu-177) prostate-specific membrane antigen radioligand therapy (PSMA-RLT) is a promising therapy for metastatic castration-resistant prostate cancer (mCRPC), but there is limited data of its efficacy and safety in Asian population. We aim to explore the clinical outcomes of Lu-177 PSMA-RLT in this population.

METHODS

We evaluated 84 patients with progressive mCRPC receiving Lu-177 PSMA-RLT between 9 May 2018 and 21 February 2022. Lu-177-PSMA-I&T was administered at 6-8-week intervals. Primary end point was overall survival (OS), and secondary end points included prostate-specific antigen (PSA) progression-free survival (PFS), PSA response rate, clinical response, toxicity assessment, and prognostic indicators.

RESULTS

The median OS and PSA PFS were 12.2 and 5.2 months, respectively. PSA decline of ≥50% was observed in 51.8% of patients. Patients achieving PSA response had longer median OS (15.0 vs. 9.5 months, p = .03) and PSA PFS (6.5 vs. 2.9 months, p < .001). Pain score improvement was seen in 19 out of 34 patients. A hematotoxicity of ≥grade 3 was observed in 13 out of 78 patients. Multivariable analyses showed that PSA velocity, alkaline phosphatase, hemoglobin (Hb), and the number of treatment cycles were independent prognostic indicators for OS. The retrospective design was the main limitation of the study.

CONCLUSIONS

Our study demonstrated a similar safety and efficacy of Lu-177 PSMA-RLT in Asian mCRPC patients compared to the existing literature. A PSA decline ≥50% was associated with longer OS and PSA PFS. Several prognostic indicators for patient outcomes were also identified.

Adverse metabolic consequences of androgen deprivation therapy (ADT) on Asian patients with prostate cancer: Primary results from the real-life experience of ADT in Asia (READT) study

BACKGROUND

Androgen deprivation therapy (ADT) use in prostate cancer (PCa) has seen a rising trend. We investigated the relationship between ADT and adverse changes in metabolic parameters in an Asian population.

METHODS

This is an international prospective multicenter single-arm cohort yielded from the real-life experience of ADT in Asia (READT) registry. Consecutive ADT-naïve patients diagnosed of PCa and started on ADT were prospectively recruited from 2016 and analyzed. Baseline patient characteristics, PCa disease status, and metabolic parameters were documented. Patients were followed up at 6-month interval for up to 5 years. Metabolic parameters including body weight, lipid profiles, and glycemic profiles were recorded and analyzed.

RESULTS

589 patients were eligible for analysis. ADT was associated with adverse glycemic profiles, being notable at 6 months upon ADT initiation and persisted beyond 1 year. Comparing to baseline, fasting glucose level and hemoglobin A1c level increased by 4.8% (p < 0.001) and 2.7% (p < 0.001), respectively. Triglycerides level was also elevated by 16.1% at 6th month and by 20.6% at 12th month compared to baseline (p < 0.001). Mean body weight was 1.09 kg above baseline at 18th month (p < 0.001).

CONCLUSION

ADT was associated with adverse metabolic parameters in terms of glycemic profiles, lipid profiles, and body weight in the Asian population. These changes developed early in the treatment and can persist beyond the first year. Regular monitoring of the biochemical profiles during treatment is paramount in safeguarding the patients' metabolic health.

Editorial for the Special Edition of Advanced Prostate Cancer: From Bench to Bedside

Prostate cancer is generally viewed as a slow-growing unaggressive cancer, yet it is one of the most commonly diagnosed cancers and a leading cause of morbidity and mortality in men around the world [...].

Genetic Testing and Its Clinical Application in Prostate Cancer Management: Consensus Statements from the Hong Kong Urological Association and Hong Kong Society of Uro-Oncology

Background

In recent years, indications for genetic testing in prostate cancer (PC) have expanded from patients with a family history of prostate and/or related cancers to those with advanced castration-resistant disease, and even to early PC patients for determination of the appropriateness of active surveillance. The current consensus aims to provide guidance to urologists, oncologists and pathologists working with Asian PC patients on who and what to test for in selected populations.

Methods

A joint consensus panel from the Hong Kong Urological Association and Hong Kong Society of Uro-Oncology was convened over a series of 5 physical and virtual meetings. A background literature search on genetic testing in PC was performed in PubMed, ClinicalKey, EBSCOHost, Ovid and ProQuest, and three working subgroups were formed to review and present the relevant evidence. Meeting agendas adopted a modified Delphi approach to ensure that discussions proceed in a structured, iterative and balanced manner, which was followed by an anonymous voting on candidate statements. Of 5 available answer options, a consensus statement was accepted if ≥ 75% of the panelists chose “Accept Completely” (Option A) or “Accept with Some Reservation” (Option B).

Results

The consensus was structured into three parts: indications for testing, testing methods, and therapeutic implications. A list of 35 candidate statements were developed, of which 31 were accepted. The statements addressed questions on the application of PC genetic testing data and guidelines to Asian patients, including patient selection for germline testing, selection of gene panel and tissue sample, provision of genetic counseling, and use of novel systemic treatments in metastatic castration-resistant PC patients.

Conclusion

This consensus provides guidance to urologists, oncologists and pathologists working with Asian patients on indications for genetic testing, testing methods and technical considerations, and associated therapeutic implications.