Is our treatment of DCIS psychologic rather than oncologic?
contributed by Michael Sabel, M.D., chief of surgical oncology at the U-M Comprehensive Cancer Center
There is a lot about DCIS, who to treat and when, that we just do not know
Editor’s note: A paper by Steven A. Narod, et al, that studied mortality among women with the breast condition ductal carcinoma in situ or DCIS was published in the Aug. 20 issue of JAMA Oncology. In its news report about the study, the New York Times suggested that the study raised doubt about the need for surgery for this condition, which for many is thought to be a precursor to cancer. In fact, the study identified several small groups of women in which DCIS definitely needs treatment because the lesions are more aggressive and therefore carry a greater risk of death. These seemingly opposite views have led to confusion among patients and doctors about treatment for DCIS. In this article, Michael Sabel, M.D., chief of surgical oncology at the U-M Comprehensive Cancer Center, discusses the study and its implications.
There has been a lot of confusion since the study was published in September examining mortality after a DCIS diagnosis. Specifically, the study looked at differences in outcome among women who were treated for DCIS by different methods. The differences among these women did not provide evidence that no treatment is an option. That would be very difficult to extrapolate.
The researchers compare patients treated by mastectomy with patients treated by lumpectomy with or without radiation. They did not demonstrate a difference in survival, though in some groups they saw some trends and possible differences between the groups. Does that support the idea that we are over treating DCIS? Perhaps, in that there are many patients who could undergo lumpectomy, and perhaps avoid radiation, as opposed to a mastectomy, and they would do fine, even if one accepted a slightly higher recurrence rate. But this doesn’t suggest that we shouldn’t treat the DCIS at all. And that is where the confusion is, perhaps leading to incorrect conclusions by the New York Times and other media.
We don’t know enough (yet) about DCIS to make a sure bet on treatment.
There is no doubt in any cancer doctor’s mind that there are many women who would go on to develop invasive breast cancer, and perhaps die of that disease, if their DCIS had not been treated. But there are also women who would never go on to develop invasive breast cancer. Why do some cases progress and others don’t? In some women, the biology of the disease is such that it might never progress to something more aggressive. In other women, perhaps they died of other causes before the lesion had the chance to progress. So while we know that we are likely over-treating DCIS, it is very difficult to identify which patients might not need treatment. The simple fact of the matter is that there is a lot about DCIS, who to treat and when, that we just do not know, at least not yet. We can make educated guesses – there are certain features that are more worrisome than others – but we still can’t reliably tell a patient that if we don’t treat your DCIS, it definitely will or will not turn into invasive cancer.
More treatment may or may not be better
Cancer doctors tend to err on the side of more aggressive treatment, and I think patients do as well. If you look at surveys of patients, when given that choice, they will often err on the side of being overly aggressive rather than under aggressive. We now see a trend towards women with breast cancer choosing to undergo bilateral mastectomies despite a lack of evidence regarding benefit. These surgeries increase the risks and complications of surgery, costs of therapy, and don’t improve outcomes. But they are strongly desired by patients for a variety of reasons and this becomes a tricky topic because patients have autonomy and have the right to decide their own therapies.
So the real message after the Narod study is not that we shouldn’t be treating patients with DCIS, but that we need more research and better identification of those patients who will benefit from more aggressive treatment, and those who we can treat less aggressively.
We also need to improve patient education so patients understand the risks and benefits of radiation, chemotherapy and surgery. They need to understand that recurrence does not necessarily mean death, as many patients, hearing the word recurrence, equate it with death and find any risk of recurrence unacceptable. This lack of understanding also leads to overtreatment.
I believe there is a real need for a national dialog from the patient/physician level on up that covers:
- What the goals of therapy are; differentiating the risks of recurrence from the risk of death.
- What the risks of recurrence of the first cancer, versus the risk of developing another cancer in someone’s lifetime are;
- Risks of bilateral mastectomy in addition to benefits;
- Whether the decision to have more aggressive treatment is the result of oncologic reasoning or psychologic stressors.