Closing the Gap in HRR Testing for Metastatic Prostate Cancer in Community Oncology

Key Takeaways:

• Homologous recombination repair (HRR) genetic testing rates among patients with metastatic prostate cancer in a large US community oncology network increased substantially between 2015 and 2024, particularly following approvals of PARP inhibitor therapies.
• Similar testing rates were observed among White and Black/African American patients, suggesting that standardized testing workflows and EHR-integrated clinical pathways may help reduce disparities in biomarker testing.
• Despite progress, testing rates remained below 50% in 2024, highlighting ongoing opportunities to improve early and consistent HRR testing through EHR-based prompts, standardized care pathways, and broader adoption of precision medicine practices.

In this interview, Helen Latimer, MPH, a research scientist at Ontada, discusses findings from the study, “Evolution of Homologous Recombination Repair (HRR) Genetic Testing by Race Among Patients With Metastatic Prostate Cancer (mPC) in a Large Community Oncology Setting in the US, 2015–2024.” The study examined trends in HRR genetic testing over a decade, highlighting increases in testing following the introduction of PARP inhibitors and exploring testing patterns across racial groups. Latimer shares insights on the role of electronic health records (EHRs), standardized testing pathways, and ongoing opportunities to expand access to biomarker testing and precision medicine in community oncology practices.

Helen Latimer, MPH: My name is Helen Latimer. I'm a research scientist here at Ontada. My work focuses primarily on generating real-world evidence in the (HRR) space. Particularly, my focus is on characterizing treatment patterns, uptake in biomarker testing, and assessing clinical outcomes in the community oncology setting.

HRR testing increased significantly after PARP inhibitors became available. What do you think is still preventing more patients from being tested in community oncology practices?

Latimer: In our study, we see a substantial increase in HRR testing over the past 10 years, particularly in years where there were PARP inhibitor therapy approvals, such as 2020 and 2023. We started to see big spikes in the number of patients tested, which I think is very optimistic. Certainly, we're seeing a reaction to the latest available therapies. Patients are being tested more commonly around these new breakthrough therapies. But there is still plenty of room for improvement. An important consideration in looking at our test results is that we looked at structured data only. There are instances where patients may have testing documented in an unstructured field, so this is a conservative estimate for what testing looks like in the community setting.

We know from other literature that there is a gap in patients being tested in the community setting vs the academic setting. Other literature has indicated that testing is more common in academic settings. So, there is certainly an opportunity for improvement. There are also certain systemic barriers happening outside of the clinic that can prevent patients from getting tested. Ultimately, what we're seeing here is a really optimistic view of how technology, such as the EHR, can be incorporated into clinical workflows to encourage a precision medicine approach in the community setting.

Your study showed similar HRR testing rates between White and Black/African American patients across many years. What role do standardized clinical pathways play in helping reduce disparities in biomarker testing?

Latimer: One of the main findings of this study was the importance of a standardized approach toward genetic testing. We know from other literature in this disease area that there have been well-documented disparities across racial and ethnic groups. This is a promising finding that demonstrates the power of technology and incorporating guideline-recommended testing into the EHR, which can help promote education across patients and providers alike.

As I mentioned before, there are systemic barriers happening outside the clinic, which is an important consideration for interpreting the data from this study. These are patients who are already being treated. We know that factors such as rural vs urban environments and socioeconomic status also play a role in how patients gain access to care. But it's promising that we're seeing in the EHR data itself that patients are experiencing similar rates of testing.

How are community oncology practices incorporating HRR testing into prostate cancer clinical pathways today, and where do you still see inconsistency in adoption?

Latimer: In general, what we're seeing across all oncology care is a focus on molecularly guided therapy, and metastatic prostate cancer is no exception. HRR testing is important in defining eligibility among patients who would benefit most from PARP inhibitor therapies. I don't think that's going to change. There will be continued advancements in this space, and providing a more detailed diagnostic picture by incorporating genetic testing as part of the routine workflow is going to continue to be important. But, as I said, there's still room for improvement.

One key takeaway from this study is how the EHR can be incorporated to ensure that testing is being provided in a systemic and standardized way across all patient populations. Something else that we didn't necessarily look at in this study, but that I think will continue to be important, is the timing of testing and making sure it's happening earlier in the patient journey.

What tools—such as EHR prompts, pathway guidance, or quality metrics—have been most effective in helping oncologists order HRR testing at the right time for patients with metastatic prostate cancer?

Latimer: This is an important question and speaks to how we think about the EHR system beyond just the documentation of diagnostic information for patients. The EHR is part of delivering care to patients and making sure that testing is being consistently documented. This is important for real-world data studies like ours, where we're able to provide additional visibility into what patients are being treated with, what their experiences are regarding access to genetic testing, how that is being documented, and where the gaps are. It's important from a holistic data perspective. Using tools like EHR prompts can help ensure a standardized approach toward testing that happens earlier in the patient journey. This way we won’t miss opportunities for patients to access targeted therapies when they will be most impactful.

Even with improvements, HRR testing rates were still under 50% in 2024. What steps are most important to help increase testing rates moving forward?

Latimer: I mentioned before that we looked only at structured data for this analysis. This is a conservative estimate of where testing is in the community setting. Other studies have noted that testing is increasing over time, but we're still not where we'd like to be.

Another important consideration is that we looked broadly at patients with metastatic prostate cancer. As a next step, if we restricted the analysis to patients with castration-resistant metastatic prostate cancer, we might observe a potentially higher testing rate among eligible patients.

That said, emphasizing the structural supports available through EHR data is going to be important in incorporating molecular testing as an aspect of routine care. The development of new therapies will continue to go in that direction, making it increasingly important to incorporate molecular testing into practice. Leveraging the technology as much as we can to ensure patients are being tested early and consistently will continue to be very important.