The 2025 American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU) was held in San Francisco, California, from February 13 to 15. It attracted top experts and scholars in the field of urology from around the world. At this conference, Oncology Frontier invited Dr. Philip Kwong from The University of Hong Kong to share his insights on precision testing and individualized management in metastatic castration-resistant prostate cancer (mCRPC). He believes that precision testing and continuous monitoring are crucial for optimizing treatment strategies for mCRPC, and he particularly emphasized the key role of genetic testing in assessing homologous recombination repair (HRR) status. His insights not only provide important guidance for clinical practice but also bring new perspectives to the individualized treatment of mCRPC.

Oncology Frontier: First of all, in the management of metastatic prostate cancer (mPC), which diagnostic and testing methods do you think are most crucial for the timely detection of metastatic castration-resistant prostate cancer (mCRPC)?

Dr. Philip Kwong: In patients with metastatic hormone-sensitive prostate cancer (mHSPC) undergoing treatment, we typically monitor disease response and progression using prostate-specific antigen (PSA) levels. Periodic imaging, especially PSMA PET-CT, is particularly useful when PSA fluctuations or rises occur. A small PSA increase may only require observation, but a significant or definite rise warrants a PSMA PET-CT to compare with baseline scans and confirm disease progression. Once progression to mCRPC is confirmed, we immediately strategize for the next treatment steps. Additionally, for patients who have not previously undergone next-generation sequencing (NGS), this would be an appropriate time to assess homologous recombination repair (HRR) status.

Oncology Frontier: In recent years, there have been continuous advancements in the treatment of mCRPC. What role do you think precision testing and individualized management play in treatment selection?

Dr. Philip Kwong: Precision testing is becoming increasingly important in mCRPC treatment selection. PARP inhibitors now hold a significant role in prostate cancer management, particularly in mCRPC. Therefore, testing for HRR mutations is critical. Some patients undergo genetic testing at diagnosis when they have a biopsy, which is beneficial as it provides a reference point. However, for patients who have not had prior testing, HRR mutation status should be assessed once they progress to mCRPC. The presence or absence of a mutation significantly influences subsequent treatment decisions. In my opinion, if a patient presents with metastatic disease at diagnosis, particularly those with high-volume disease, it is prudent to conduct HRR or NGS testing early to better prepare for future treatment needs.

Oncology Frontier: During the progression of mPC to mCRPC, how do you view the importance of continuous testing and dynamic monitoring?

Dr. Philip Kwong: The importance of continuous testing depends on the timing and progression of the disease. Genetic mutations may evolve throughout the course of the disease, particularly regarding HRR status. If there is a long interval between the initial genetic test and the development of mCRPC, retesting may be necessary. Additionally, if an initial test was negative and conducted via liquid biopsy, I recommend retesting, as liquid biopsies sometimes yield false-negative results. Reassessing genetic mutations at key progression points is crucial for guiding treatment decisions effectively.