Expert discusses meta-analysis of prostate radiotherapy

In this video, Scott Morgan, MD, MSc, FRCPC, discusses questions that arise from the European Urology paper, “Prostate Radiotherapy in Low-volume Metastatic Hormone-sensitive Prostate Cancer: A Network Meta-analysis.” Morgan is a radiation oncologist at The Ottawa Hospital Cancer Centre and an associate professor of radiation oncology at the University of Ottawa, Ontario, Canada.

Transcription:

What questions arise from this study?

I think we have to acknowledge that a network meta-analysis relies on some indirect comparisons. And of course, we would prefer to have direct comparisons to guide our practice. So there are some limitations in this analysis. Ideally, I think we would have a dedicated, large-scale randomized trial that would definitively address this question. So in other words, in patients who are presenting with low-volume, metastatic prostate cancer, it would be ideal to have a trial where patients receiving ADT and an AR pathway inhibitor are randomized to receive either prostate radiotherapy or not. I'm aware of 1 trial that's currently accruing in the US, SWOG 1802, that may shed some further light on this once it ultimately reports. It's not limited to patients with low-volume disease, and also the local therapy that can be used in that trial can be either prostatectomy or prostate radiotherapy, so it's a bit more heterogeneous in those aspects. But I think it'll still be very much of interest once it completes accrual and matures and reports. Another limitation, I think, in this analysis is that we relied on aggregate summary data from the trials. It would be preferable to do a network meta-analysis with individual patient data. You can much more cleanly account in with individual patient data on patients that received docetaxel as part of their initial treatment, and it would allow a clearer analysis in terms of patients with de novo presentation. So, I think you could arrive at a more precise effect estimates with an individual patient data network meta-analysis. We didn't have access to individual patient data, and I'm not sure really whether we will ever see an individual patient data analysis that takes account of all the data from all these trials, including industry trials. We might have an IPD meta-analysis that includes the academic trials, and that would certainly be welcomed, though. And then in terms of in this disease space, to me, that the burning question...is about the value for metastasis-directed local therapy and oligometastasis-directed local therapy; in particular, SBRT in this population. And so that's the subject of a number of ongoing randomized trials. So, in my view, at present in patients that have low-volume oligometastatic de novo metastatic prostate cancer, it's really an unknown whether comprehensive SBRT or other local therapy directed at oligomets improves survival. So, in my view, it really shouldn't be routinely used off trial, especially where trials are available.

This transcription was edited for clarity.