27. Do you tell patients with DCIS that they have breast cancer?

Monica Morrow, MD

I think that it is naïve not to tell patients with DCIS anything about the words "breast cancer," because someone will tell them that they have cancer — usually their insurance company. I tell patients with DCIS that we call DCIS either the earliest form of breast cancer that we can find or a pre-cancerous problem. I explain that the reason for this difference in terms is because technically the essential characteristic of cancer is that it can spread to other parts of the body, and DCIS lacks that characteristic. That gets across the key message that I want to give them about DCIS. These women have mastectomies, or they have lumpectomies and radiation, and half of them are afraid they’re going to need chemotherapy. So, I think that it is critically important to differentiate what is different about DCIS than invasive breast cancer.

28. About what fraction of your patients with DCIS receive tamoxifen?

Monica Morrow, MD

It is surprising that such a high fraction of patients are receiving tamoxifen. DCIS is like the prevention setting — it’s a risk-benefit calculation: How much benefit do you need to make it acceptable to take a drug for five years with side effects? In my practice, the number is more in the 40 to 50 percent range, even though I offer it to the overwhelming majority of patients with DCIS.

Nancy Davidson, MD

This is a bit surprising, because I think my practice is more like 50-50. That probably also reflects the tertiary type of patients I see — they’re searchers into tertiary care kinds of issues, and in some cases, they’ve received a recommendation of tamoxifen and don’t want to take it.

29. The patient is a 78-year-old otherwise healthy woman with a 1 centimeter focus of comedo DCIS and margins of 1 centimeter. She wishes to have breast conservation and radiotherapy. What systemic therapy, if any, would you recommend?

Monica Morrow, MD

This woman is 78 years old with a widely excised DCIS, and she’s got a ten-year risk of local failure with radiotherapy that maybe is in the 8 percent range. The magnitude of benefit you’re going to get from tamoxifen in this woman is relatively low, and she certainly is in an age group that puts her at risk for the side effects. So, I might perhaps be less enthusiastic than the audience about treating this patient. It really depends on her overall state of health, which we don’t know much about.

Nancy Davidson, MD

My enthusiasm for giving her tamoxifen would be moderate. I would certainly want to bring it to her attention, and I would be happy to prescribe it. But, I would imagine that if I had 10 of these women come in a row, probably not more than half of them would take it when they heard about what the benefits are and the potential downside.

30. Would you prescribe chemotherapy for a patient with DCIS with a positive axillary node on H&E staining?

Monica Morrow, MD

If you have a truly H&E histologically positive node, you don’t have DCIS, but invasive breast cancer that the pathologist didn’t sample. So, if the metastasis was discovered by H&E staining, I completely agree with the people who support chemotherapy. If we’re talking about an immunohistochemical lesion in a sentinel node, since I don’t think we know what those mean, I would say no.

Nancy Davidson, MD

If the node is positive by H&E, I would feel reasonably comfortable calling this a node-positive breast cancer. If this is the kind of nodal metastasis where the pathologist can show it to me, and I’m convinced, I would treat this woman as node-positive. It is much more common to see a DCIS where the sentinel node has been done and there are three brown IHC cells in one cut, and that’s a lot tougher and turns out to be very individual-patient driven. The last patient I had like this had a 7 centimeter DCIS at the age of 36. She opted for chemotherapy, but I can imagine that that would be the exception, rather than the rule. It was driven largely by the very large size of her DCIS and her youth.

All of the cooperative group trials require that node positivity be defined by H&E-positive lymph nodes. They don’t allow cytokeratin-positive lymph nodes, for example, to qualify as node-positive. That speaks to our uncertainty about these immunohistochemistry findings.

31. What is the minimum margin width that should be obtained if you are considering excision alone as treatment for DCIS?

Monica Morrow, MD

The idea that there is a minimum margin that you can say all patients have to have is silly. It depends what you see when you look at that DCIS under the microscope. It depends what the patient’s age is. It depends how many margins there are, and what margin it is. Certainly, we radiate people with anterior and posterior margins less than a millimeter when there’s no more breast tissue there without thinking about it twice. If I had every single one of my margins in the breast of a millimeter or less, then I’d be worried.

32. Women under age 50 with DCIS who are treated with breast preservation have more than double the chance of recurring locally when compared with women who are more than 60 years of age.

Monica Morrow, MD

There is an increasing body of evidence demonstrating that age under 50 is associated with an increased risk of local failure for women with DCIS. That was best demonstrated in the NSABP tamoxifen trial, in which both the women who did and did not receive tamoxifen had higher local failure rates under age 50. All of these patients had excision and radiation. You could quibble about whether it’s exactly twice the failure rate, but it’s certainly higher.