Personalizing Prostate Cancer Surveillance: Insights from Canary PASS

Announcer:
You’re listening to On the Frontlines of Prostate Cancer on ReachMD. On this episode, we’ll hear from Dr. Lisa Newcomb, who’s the Deputy Director of the Canary PASS study at the University of Washington and Fred Hutchinson Cancer Center in Seattle. She’ll be discussing findings on personalized active surveillance through risk stratification in patients with early-stage prostate cancer. Here’s Dr. Newcomb now.

Dr. Newcomb:
So the Canary Prostate Active Surveillance Study, or Canary PASS, is a multicenter cohort, and admittedly, setting up a multicenter cohort and accruing patients in a standardized fashion is challenging. We have an amazing coordinating center that helped develop methods and ways to collect data and biospecimens in a standardized and robust manner, and to maintain both adherence to the protocol and high-quality data, we conducted numerous in-person site visits, and we monitor study metrics very closely.

So our group has found that routine clinical variables, such as Gleason score or Gleason Grade Group, PSA, the amount of cancer present in a biopsy prostate volume, or PSA density can be used very well to stratify risk in early-stage prostate cancer, and it’s challenging to find biomarkers that improve that risk stratification. However, that risk stratification with clinical variables is not perfect, and we’re continuing to explore ways to improve it.

So one notable finding that we report in the JAMA publication is that 75 percent of the 21 patients who did develop metastasis upgraded or retreated after the confirmatory biopsy or the first biopsy after diagnosis. Again, this is about a year after diagnosis. And this suggests that improvements in diagnostic tools, such as MRI, will further improve selection of patients that can safely use active surveillance, and this should further reduce adverse outcomes. 

So looking to the future, we are really focusing on better stratifying the risk of patients diagnosed with favorable-risk prostate cancer. We’ve learned from our current study that at least 50 percent of the men using active surveillance do not need as frequent biopsies as they have been receiving, at least in our protocol-directed cohort, so we’re focusing on ways to better identify those men early—right after diagnosis—so that they can be spared the morbidities of prostate biopsies. Likewise, there’s 10 to 15 percent who have reclassification to a more aggressive cancer, recur after treatment, or even develop metastasis, and we would like to identify those men even earlier so that they could be treated earlier, further reducing adverse outcomes.

So to improve risk stratification to accomplish both of these goals, we’re looking at a number of biomarkers—tissue-based, blood-based, and urine-based. We’re doing a deep dive into histologic features, such as cribriform. There’s a fair amount of evidence that Gleason pattern 4 disease that has cribriform has worse outcomes, and the pattern 4 that does not have cribriform has fairly indolent outcomes. We’re working with a number of companies to evaluate AI strategies for histology and MR imaging, and hopefully, these will be useful in further surveillance protocols. So in conclusion, I think that future surveillance protocols will continue to be more personalized, and there won’t be one-size-fits-all protocol.

Announcer:
That was Dr. Lisa Newcomb sharing findings from the Canary PASS study on risk stratification in early-stage prostate cancer. To access this and other episodes in our series, visit On the Frontlines of Prostate Cancer on ReachMD.com, where you can Be Part of the Knowledge. Thanks for listening!