We come back to the importance of explaining that it is the most crucial treatment for this subtype of breast cancer. Again, information is really key.
Sometimes I also use the argument with my patients that the alternative is even worse because if you use an aromatase inhibitor, and you have to use an LHRH agonist, then the implications for your sexual life are even worse. That’s how I try to convince them to stay on tamoxifen.
Let’s finalize with a couple of words on metastatic breast cancer in male patients. Sharon, I’ll start with you again. Is there any difference in the management if you have a patient with metastatic, ER-positive, HER2-negative disease? How do you treat? How do you sequence the available therapies? Is it different from the female patient?
Dr. Giordano: I’d say that, big picture, it’s quite similar. Again, most of the men have hormone receptor–positive disease, so really, the mainstay of treatment and the first treatments are going to be endocrine therapies. We’ll sequence through the endocrine therapies like we do in women. When using aromatase inhibitors, I typically would add a GnRH agonist to that, and I have had that be a very successful therapy, along now with the CDK inhibitors that are also approved.
I don’t think the studies of CDK inhibitors included male patients, but at least palbociclib actually was approved in the United States, based on some real-world evidence of its efficacy. Anecdotally, again, in my clinical practice, that tends to be a really powerful combination of leuprolide, an aromatase inhibitor, and a CDK inhibitor.
I think there’s less information about drugs like fulvestrant, whether that would benefit from combination with a GnRH agonist or whether those should be given as single agents. We just don’t really know. We have a few case series out there.
Similar to the early breast cancer setting, I think it’s really important to remember to check for BRCA1 and BRCA2 mutations. PARP inhibitors could be a part of the treatment plan if those underlying germline mutations are found. Generally, we’re following a similar sequence of endocrine therapies and then, eventually, chemotherapy.
Dr. Cardoso: Maybe, Oliver, you’re also seeing that one consistent finding in the biology study is the importance of the AKT/PI3K/mTOR pathway in male patients with breast cancer, because we now have at least two classes of agents to tackle this pathway. Again, anecdotally – we’re not talking about trials – I’ve been seeing quite interesting responses, for example, to everolimus combined with endocrine therapy.
We have a little less experience with the PI3K inhibitor, but that’s just because of accessibility to the drug. I think this combination is also something to keep in mind that can be quite effective in these patients.
Dr. Bogler: I agree. Those findings are exciting in the context of dealing with something as difficult as metastatic breast cancer. It’s good to know that there’s some information coming and opportunities and options, hopefully, down the road for men facing that problem.
Dr. Cardoso: Sharon, although small numbers, in these cases where there is HER2-positive disease, you would also use the new anti-HER2 agents and more or less the same sequence, right?
Dr. Giordano: Absolutely. It’s not particularly data driven, but yes, I would. If it’s a HER2-positive tumor, I would use the same HER2-targeted therapies that are used for women with breast cancer.