Lutetium-177 PSMA-617 improves symptoms related to bone metastasis in prostate cancer

Prostate-specific membrane antigen (PSMA) radioligand therapy for prostate cancer has demonstrated many promising results in previous trials, such as improved progression-free survival, overall survival, and patient-reported outcomes.

Brian D. Gonzalez, PhD

The investigators of a recent study sought to determine whether those improvements are consistent with bone-metastasis-related outcomes. In this interview, Brian D. Gonzalez, PhD, shares results that were presented at the 2022 ASCO Genitourinary Cancers Symposium from this study.¹ Specifically, he highlights the fact that patients who received Lutetium-177 PSMA-617 reported lower levels of bone-metastasis-related pain. Gonzalez is a quality of life researcher at Moffitt Cancer Center in Tampa, Florida.

Please discuss the background for this study.

There are several types of treatments for metastatic castrate-resistant prostate cancer. One of the new emerging treatments is called targeted radionuclide therapy. This project studied patient-reported outcomes in an early-phase trial of men receiving PSMA-targeted radionuclide therapy, and that trial had previously shown improvements in survival, but also patient-reported outcomes. This project was focused on bone-metastasis-related pain and quality of life pain.

What were the notable findings of this study? Were any of them surprising to you or your co-authors?

We found that men who completed the survey on bone-metastasis-related pain and quality of life reported improvements, on average, in bone-metastasis-related pain and their ability to function despite that pain. A caveat is that there were several patients who were unable to complete the survey in this longitudinal study because some of them had passed away, or some of them felt unwell or were unwilling or unable to attend visits. But those that did complete the surveys generally reported average improvements in bone-metastasis-related pain and ability to function despite that pain. We looked at not only whether the changes were statistically significant, but also whether the improvements were clinically significant, meaning whether patients would have noticed that level of improvement that they reported. Was it a meaningful improvement to them, based on published cutoff scores for that kind of improvement? What we found was that at follow up, so this is 6 or 12 weeks after the final injection, over a third of [men] reported clinically significant improvement in these outcomes, which was an encouraging sign for these patients.

Is there further research on this topic plan? If so, what will its focus be?

This project is funded by a Department of Defense award and is a collaboration with colleagues throughout the world. In this project, we're developing a new patient-reported outcomes measure for men receiving targeted radionuclide therapy for prostate cancer. This recent study is informing some of the selection of symptoms or toxicities that we should include as part of this new measure.

What is the take-home message for the practicing urologist?

The take-home message is that men who are able to receive this treatment—targeted radionuclide therapy for prostate cancer—generally report improvements in bone-metastasis-elated pain and their ability to function despite that pain. That's an encouraging sign. But it's an important finding using patient-reported outcomes, which are often deemed the highest quality data we can get about patients' experience.

Reference

1. Gonzalez BD, Brownstein NC, Fan W, et al. Improvements in symptoms related to bone metastasis in recipients of Lutetium-177 PSMA-617 for prostate cancer. Paper presented at: 2022 ASCO Genitourinary Cancers Symposium; February 17-19, 2022; San Francisco, California. Abstract #96