A new study found a blood test could identify some women at higher risk of recurrence of early triple negative breast cancer months before it became detectable through standard follow-up.
But there’s a caveat.
Austin-based oncologist and breast cancer specialist Dr. Debra Patt talked about this with KERA’s Sam Baker.
Dr. Patt: They're looking at a person's breast cancer that they have had and looking for early recurrence by looking for mutational markers in the bloodstream. And it's a very sensitive test.
We've learned from the many studies that have looked at cell-free DNA and mutational analysis to detect early recurrence, is it does detect early reoccurrence. It has been demonstrated, particularly in triple negative breast cancer.
But what it has not yet shown is a difference in survival because patients have implemented a strategy to augment their screening.
So, what happens is you have a cancer that's detected so a patient will get appropriate surgery, lumpectomy or mastectomy for their breast cancer. You know, whatever appropriate therapy they have, sometimes that's radiation therapy, sometimes that's chemotherapy or a pill to block estrogen, and then they're really in follow-up essentially, and we see them regularly in follow up to detect recurrence.
Baker: This gives you that information earlier than you would simply relying on imaging, biopsies, etc?
Dr. Patt: Yes. In patients who have early stage breast cancer, we don't do other routine imaging at regular intervals. And so what would precipitate imaging would be either a symptom or a laboratory abnormality to follow women with early stage cancer. There's really not routine imaging.
Patients don't have PET scans or CAT scans at regular intervals. And so, if you have a cell-free DNA signal that shows you that cancer might be present, it might prompt you to do imaging that you might not otherwise do, that then gives you insight into early evidence for metastasis.
Baker: This isn't what's called a guidelines-based test. It's not directed by established clinical or professional practice rules. So what would this mean for patients?
Dr. Patt: Sometimes people choose to be followed every three months in high risk and then they can track it over time. And then if they see a spike that it looks like there's a cell-free DNA spike in their bloodstream, it might prompt you to do additional workup.
Because this is not a guideline-based test, really it's a collaborative discussion, usually between doctors and patients, whether you undergo testing at all, because oftentimes because it's not guideline- based, insurance does not cover it.
And also then how you deal with the test results. And I think you have to talk to patients about that early on so you can sort of make a determination about how you're going to use the test. And that's important.
But what I would say more broadly, Sam, is I think that it's a really exciting time in molecular diagnostics in cancer because our ability to do this fine-tooth comb kind of work, essentially looking for a needle in the haystack in a much more sensitive and specific way, we increase our capability as cancer specialists to have early detection of recurrent cancer. And also there is pioneering work in trying to augment traditional screening for cancer.
It's really exciting because from a public health perspective, when I wear my public health at Texas Oncology, I can see that the age distribution of the population is changing. Cancer is quite common, one out of two men and one out three women in their lifetime get cancer. And our ability to really guide, direct control and cure cancer is best when it's caught early.
And so I see this really exciting continuous development of our potential for technology to serve patients and help them live without cancer.
