The recent study findings that women diagnosed with ductal carcinoma in situ had a low breast cancer–specific mortality and that preventing ipsilateral recurrences did not prevent breast cancer mortality¹ might lead some women diagnosed with ductal carcinoma in situ to question the need for treatment aimed at preventing recurrences. However, it does not mean that most women will choose to opt out of that treatment.

“Surgeons are more likely, believe it or not, to recommend less surgery, lumpectomy, and patients are more likely to want more surgery, bilateral mastectomy,” Monica Morrow, MD, Chief, Breast Service, Memorial Sloan Kettering Cancer Center, New York, told The ASCO Post. “The approach to that conflict is to help patients understand what will and won’t prolong their survival. But even when you have that conversation, it is just an idea that is hard to get rid of—that bigger surgery doesn’t cure more cancer,” Dr. Morrow.

Commenting on the study on the PBS NewsHour, Dr. Morrow said, “A critical finding of this study is how good the prognosis for ductal carcinoma in situ is, and women should be reassured, because we know that women with ductal carcinoma in situ estimate their risk of dying of breast cancer to be as high as 30%. And this study says that’s just simply not true.”²

A Conversation With the Patient

“The way we determine whether anyone is a candidate for lumpectomy with radiotherapy or mastectomy is based on the amount of ductal carcinoma in situ in the breasts relative to the size of the breasts. So can you do a lumpectomy, remove all the ductal carcinoma in situ with a margin of normal tissue around it, and still leave a breast that looks relatively normal? If the answer to that question is yes, that is pretty much the only thing that determines candidacy for lumpectomy,” Dr. Morrow said.

“Then if there are patients who based on the characteristics of the ductal carcinoma in situ and age are going to need radiation, is there any reason that they can’t receive radiation? Most people can receive radiation. If you’ve had prior radiation to the breast area, you can’t. If you have some uncommon diseases like active lupus or scleroderma, we generally don’t give radiation. But other than that, most people other than pregnant women can get radiation,” Dr. Morrow explained. “So then it boils down to a conversation with the patient about what the risks and benefits of the two treatments are and which one better meets her needs if she is eligible for both.”

Recurrence Can Be Psychologically Devastating

Recurrence in the breast, even if it is not associated with death, can be “a psychologically devastating complication” for many women, Dr. Morrow noted. “They want to avoid experiencing breast cancer again, and so they are willing to do radiotherapy. Now, do I think all women with ductal carcinoma in situ need radiotherapy? No. I think there are many women with small, low-grade ductal carcinoma in situ, particularly postmenopausal women, where the risk of recurrence is extremely low with radiation, and that should be explained to them. But we also have new clinical trials showing that even in those very low-risk women, the risk of cancer recurrence in the breast is further reduced with radiation.”

Women who have ductal carcinoma in situ are at increased risk of developing contralateral breast cancer. “That risk can be reduced with tamoxifen in premenopausal women and in postmenopausal women with tamoxifen, or raloxifene [Evista], or aromatase inhibitors,” Dr. Morrow noted. Currently, however, “the use of endocrine therapy is quite low in women with ductal carcinoma in situ.” ■

Disclosure: Dr. Morrow reported no potential conflicts of interest.

References

1. Narod SA, Iqbal J, Giannakeas V, et al: Breast cancer mortality after a diagnosis of ductal carcinoma in situ. JAMA Oncol. August 20, 2015 (early release online).

2. Study raises questions about treatment for early breast cancer. PBS NewsHour, August 20, 2015.