Study: Chemo Unnecessary In Many Cases Of Early-Stage Breast Cancer
Cancer was once referred to as “The Big C.” Then along came another C. A miracle, really, for so many: chemotherapy. It attacked cancers, prevented them from spreading, and helped so many people into remission. But, of course, it also has debilitating side effects.
Now, a landmark study, sponsored by the National Cancer Institute and published in the New England Journal of Medicine, finds that many women with early stage breast cancer can skip chemotherapy and do just fine.
The study looked at the effectiveness of a test, called Oncotype DX, that has been around for about a decade, in gauging how likely a patient’s tumor is to respond to hormone-blocking drugs alone. The study found that for those who scored low risk on the test and who did not do chemotherapy, 99 percent had not relapsed after five years, and 98 percent were still alive.
Some doctors are taking it as the latest piece of evidence that they may be overtreating certain cancers. Here & Now’s Robin Young talks to Dr. Shelley Hwang, chief of breast surgery at Duke University, about the shift in how the medical community is talking about and treating breast cancer.
On the types of cancer that aren’t responsive to chemotherapy
“The types of cancers the studies are looking at are women who have the most common kind of breast cancer, which is estrogen-receptor-positive breast cancer. This very special class of tumors tends to be slow growing and therefore tends to benefit less from chemotherapy, they are driven by estrogens. So the strategy is, by depleting estrogen from these tumors, we can slow down growth and hopefully prevent any mortality from these cancers. The question in this study was, if we took a group of women who had these very favorable prognosis tumors, we might be able to choose a group of women who responds so well to endocrine therapy alone that we can omit chemotherapy as part of their treatment.”
On the Oncotype DX cancer test
“It measures genes that determine the aggressive nature of the tumor. It gives us some indication as to which tumors may have a good enough prognosis even without chemotherapy. The standard treatment now is for many patients to give endocrine therapy and chemotherapy for patients who are at intermediate risk or high risk, but what this study shows us is that if patients are very low risk – at five years patients have less than 2 percent chance of recurrence even without chemotherapy. So I think this confirms what we’ve always wanted to do – let the biology drive the treatment decisions rather than just recommend the same treatment for everybody.”
On what happens when someone has chemotherapy when they don’t need it
“First of all chemotherapy is used to treat a wide variety of cancers, and the side effects from chemotherapy have never been as treatable as they are now. Nevertheless, it’s still used to treat a large variety of tumors including breast cancer, as you say it’s a medication that generally goes through an IV, it’s given over four to six months generally. The side effects, the first thing, they lose their hair, there may be some nausea, fatigue, lots of side effects including numbness in hands and feet, and long term side effects as well. Those are toxicities that if the chemotherapy is beneficial, many patients are willing to undergo, certainly many of us recommend it. But if they’re not going to benefit substantially, then those are toxicities the patient doesn’t have to be exposed to.”
On the risks associated with any treatment
“I think it’s really important for the public to know that even when patients follow all the recommendations the physicians give you, there’s always a chance of recurrence. There’s certainly patients that decline any treatment we offer, and still do very well. And we are really at the beginning of trying to understand which kinds of tumors may benefit from very little treatment and which tumors we need to intervene early and aggressively. This is one step in the right direction. But I think patients need to understand that all the treatments we give them are meant to cure, but in the end all the treatments just give a proportional risk reduction – it reduces the risk the cancers going to come back – but much of what we do, it doesn’t eliminate that risk completely. So the patients in the study, 2 percent did have a recurrence, but even if they did have chemotherapy, that wouldn’t have prevented them from having that recurrence. As society, we as stakeholders need to be very comfortable in accepting that risk.”
On the decision to choose a certain treatment
“The decision about treatment, particularly for breast cancer, we’re really far ahead of many other kinds of cancers – it involves a very thoughtful conversation between the physician and the patient. And it also requires some understanding of the kind of risk you’re comfortable taking on in your life. There may be many women out there who are willing to take any treatment, including chemotherapy, for even a very small increase in benefit. So there are lots of treatments we give for maybe a 1 or 2 percent benefit in mortality. And for some women the toxicities of treatment are worth that and I think that’s absolutely the right decision for them. But this gives us evidence about what could happen if they didn’t have chemotherapy and this allows us to be a little more courageous about thinking about taking some of those treatments, making them less critically important as part of the treatment for these patients. There will always be patients who want to do the most – chemotherapy, double mastectomy – but I think it’s really in the context of fear, and if we can provide data which gives them some idea of how small the benefit might be from some of the very aggressive treatments that are part of what is offered, then they might choose to make different decisions.”
- Dr. Shelley Hwang, chief of breast surgery at Duke University.
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