Genetic Testing Is Becoming an Important Conversation in Metastatic Prostate Cancer

Meredith Donahue, APRN-BC

The landscape of metastatic prostate cancer has been drastically changed by the introduction of lutetium Lu 177 (Pluvicto), triplet-therapy combinations, and PARP inhibitors, according to Meredith Donahue, APRN-BC.

“It is just amazing to see how much has changed just since I've been in the field. When I started, it was enzalutamide [Xtandi] and abiraterone [Zytiga] and docetaxel. That that was it,” said Donahue, who is a nurse practitioner in the department of urology at Vanderbilt University.

“Now we've got enzalutamide and abiraterone, apalutamide [Erleada], and darolutamide [Nubeqa], [which are] all great therapies that we use,” she said. “I think the biggest change has been the individualized care for patients. That comes back to genetics, with germline and somatic testing and [new] targeted therapies.”

Donahue will be speaking on new and emerging therapies in metastatic prostate cancer as part of a summit with Vanderbilt University. In an interview with Oncology Nursing News, she shared her optimism on the broadening array of treatment options for this population and underscored the importance of understanding precision medicine as a nurse specializing in this field.

Oncology Nursing News: What new emerging treatments are you most optimistic about and why?

Donahue: It is hard to talk about advanced prostate cancer without talking about lutetium-177. The precursor to lutetium is PSMA PET scans. We have been doing those for a couple of years now, and that is something else that has just changed the game of advanced prostate cancer in catching metastatic disease earlier.

One emerging treatment is triplet therapy with androgen deprivation therapy [ADT], a novel hormone therapy and docetaxel. I am most excited about this because of the data in improved overall survival [OS]. I think it really is going to change the way we do things in a good way.

Could you speak to the data behind some of the newer therapies that you will be presenting on?

Starting with triplet therapy with darolutamide, the ARASENs trial [NCT02799602] showed an improvement in OS, compared to men who got ADT plus docetaxel plus placebo.

Looking at triplet therapy with abiraterone, the PEACE-1 trial [NCT01957436] showed improved OS in men with high-volume metastatic disease—which is where these therapies play the biggest role: in that metastatic, high-volume, hormone sensitive setting.

Improving overall survival is a big thing. Men who received those triplet therapies upfront lived longer than men who did not receive the triplet therapy.

Certainly, each of those therapies have their own toxicities. That is very important to pay attention to. While these therapies might have the best overall survival outcomes, we also think about the patient and what we are giving them. It is a lot different giving these triplet therapies to a healthy 65-year-old man vs an 88-year-old patient who has had a heart attack and diabetes and all those things. We can only take data so far—what really matters is the patient sitting in front of you.

Have you seen the shift to triplet therapy change outcomes in your practice?

I had a patient who presented to my clinic, maybe a month ago, with an elevated PSA of 40. We biopsied and scanned him. [He had] diffuse metastatic prostate cancer. We quickly got him started on ADT with an antagonist, and now, he is starting triplet therapy this week. We’re yet to see how he does [but] I think he is going to do really well.

It was encouraging to me to see how quickly we could get that process going.

Getting tissue, getting diagnosis, [and getting him] on triplet therapy within a month is certainly overwhelming for a patient, but for someone like him who is a relatively young, in his 60s, working, healthy guy—we want to treat him aggressively.

Will you be talking about PARP inhibitors? From a nursing perspective, what are some key things to know about this class of drugs?

The big thing—especially from a nursing perspective—to know about PARP inhibitors is that it requires genetic testing. Understanding germline vs somatic testing, understanding how we get those—is it blood or is it tissue—and just how to navigate genetic testing and knowing when do we incorporate genetic counselors, is the big takeaway. Genetic testing can sound really scary to some patients, but helping patients understand the importance of it [has become key].

How do you talk to patients about genetic testing? What are the implications of genetic testing in prostate cancer?

Usually, they have no idea what we are talking about. Sometimes, patients will [ask], “What are you doing with that information?” We help them understand that it is anonymous, and it is for their treatment—it is not for anything else. But, usually, the response I get is, “I have no idea what you're talking about. Please explain more.” That is why it is important for nurses who are doing that education, who are drawing and coordinating those labs, to understand why we're doing it, what it is, and how we're doing it.

I have a patient who has not progressed. We treated him locally with radical prostatectomy. He is young—in his 40s—with significant family history. Given his diagnosis under age 55, and his family history, at his first postoperation visit, we were sent him to germline testing, and he came back with a BRCA2 mutation.

With genetic testing, of course PARP inhibitor [eligibility] is important, but it is also important information for the patient and their families. So, we got him right into genetic counseling, and they can counsel him on, does he need to start routine colonoscopies earlier? Does he need skin checks earlier? For his children, when or what do they need to start doing?

Genetic testing is not just about getting therapies but also [providing] information for the patients and their whole family.