Manuel A. Torres-Salichs MD,FACS Surgical Oncology, Breast Surgeon

Edileidis Tarrio, ARNP-BC, OCN





Surgical Treatment Options

Standard Treatment:
Since there is uncertainty as to which patients will develop a more aggressive breast cancer, all patients are treated as soon as the diagnosis is made. The standard treatment of DCIS includes a lumpectomy (preserving the breast) with radiation therapy or a mastectomy (complete removal of the breast).

Mastectomy versus Lumpectomy:


Mastectomy Lumpectomy


Not every patient is a candidate for breast preservation. The decision of one versus the other depends on several factors. The tumor size in relation to the breast size is one important factor. The goal is to remove the tumor in its entirety and preserve the cosmesis of the breast. The advantage of doing breast conservation or a lumpectomy is one and only, the preservation of the breast. Breast conserving therapy implies complete removal of the breast tumor with a concentric margin of surrounding healthy tissue in a cosmetically acceptable manner. It is imperative to achieve negative margins.

This means the very edge of the cut surface of the specimen needs to be free of cancer cells. A literature review shows up to a 48% incidence of positive margins after a lumpectomy. This means there is a need to go back for a second surgery in order to clear the breast of cancer cells. A positive margin is associated with a high incidence of recurrence. In other words, there is a possibility of the cancer coming back in the future. The decision to preserve the breast implies a risk for "in breast recurrence" (cancer returning back in the future), or a new primary breast cancer in the same breast. This risk is approximately 15% within ten years. A mastectomy is needed should the tumor recur.


The illustration on the left shows a lumpectomy with negative margins. The tumor is removed with a concentric rim of normal breast tissue around the cancer. On the right, we have an example of a lumpectomy with positive margins. The cancer cells touch one of the edges of the tissue removed. This patient needs to return back to the operating room to clear the margins.

Negative Margins Positive Margins



Mastectomy is also an option in the treatment of DCIS. A mastectomy is sometimes recommended due to the extent of the disease. It does not necessarily reflect the aggressiveness of the cancer cells, but their distribution throughout the breast. A woman may choose this option over a lumpectomy if she is unwilling to undergo radiation therapy. We discussed earlier that DCIS means cancer cells are within the duct and do not have the potential to spread. It is important to acknowledge that after diagnosing DCIS by a needle core biopsy (streotactic biopsy) there is the possibility of finding an invasive cancer in approximately 10% to 20% of cases. With this in mind, it is recommended to proceed with a sentinel node biopsy if a mastectomy has been elected. This will avoid the need of an axillary node dissection in the case that the mastectomy specimen reveals an invasive component. We also recommend a sentinel node biopsy in selective breast conserving cases depending on tumor characteristics.


This illustrates the concept of multicentric disease. Multiple tumor foci are spread throughout the breast. This is confirmed by either breast imaging studies or tissue biopsy. This patient should be treated with a mastectomy.


Mammogram showing diffuse microcalcifications in a patient with DCIS. Breast conservation is not an option due to the extent of the disease throughout the breast.


Radiation Therapy in Ductal Carcinoma in Situ


Although there have been no studies conducted that directly compare breast-conserving therapy to mastectomy with DCIS, numerous retrospective studies have demonstrated identical cause-specific survival to mastectomy. Despite complete resection of the tumor during lumpectomy, some women with DCIS remain at a higher risk of recurrence unless they undergo additional radiation therapy. DCIS is known to be multicentric (independent tumors foci away from the main tumor). Women with DCIS can be left with these tumor foci despite obtaining negative resection margins (no tumor cells at the very cut edge of the surgical specimen). These cells are not necessarily identified by breast imaging studies. The intent of radiation therapy delivery in DCIS is to eradicate subclinical foci of residual disease and to minimize the risk for local recurrence following surgery.

Radiation therapy will treat these residual tumors and will reduce the risk for local recurrence (tumor returning back in the breast). Overall, in patients who undergo radiation therapy, the relative risk of a recurrence by either DCIS or invasive cancer is reduced by 50%.

There is a subset of patients in whom radiation therapy may not be beneficial. There are other cases where DCIS is an indolent disease and will not progress to invasive cancer. Our main limitation is the ability to be able to identify this group of patients in order to spare them from treatment (surgery and radiation therapy).On the basis of the known data; the general recommendation is that women with resected DICS should be offered radiation therapy to reduce the risk for local recurrence.


Microscopic Disease:
Both ductal carcinoma in situ (DCIS) and invasive cancer are known to be multifocal and multicentric. Small foci of tumor can be left behind despite obtaining negative lumpectomy margins. These cancer cells are microscopic and are not seen by breast imaging studies. The goal of radiation therapy is to eradicate this residual disease and decrease the incidence of local recurrence.