From Our Experts

Key Facts to Know about Breast Cancer Surgery

Originally published October 16, 2023

Last updated October 16, 2023

Reading Time: 4 minutes

A diverge group of women wearing breast cancer awareness ribbons standing together outside

Emily Siegel, MD, a breast surgical oncologist at USC Norris Comprehensive Cancer Center, part of Keck Medicine of USC, shares important facts about surgical treatment for breast cancer.

If you’ve been diagnosed with breast cancer and your treatment plan includes surgery, your first, second, third and even fourth thoughts may undoubtedly be scary: Surgery. Cancer surgery. Breast cancer surgery. My breast cancer surgery. However, knowing key facts about surgical treatment for breast cancer, including the difference between a lumpectomy and mastectomy, may be helpful as you prepare for the treatment journey ahead.

Breast cancer care is not one-size-fits-all.

First and foremost, not all cancers are treated the same way. In fact, not all breast cancers are treated the same way. So, it’s important to keep in mind that your cancer treatment plan may vary from what you read online or what your friends and family members have undergone, even if they’ve received breast cancer care. Differences in treatment plans do not mean you’re being treated incorrectly or that your family and friends were treated improperly. Instead, I advise my patients to think about breast cancer as diverse, which requires that treatment plans be tailored and personalized to every unique person’s particular cancer.

Lumpectomy vs. mastectomy: What is the difference?

The goals of any cancer operation are to remove the cancer and determine if it has spread. With breast cancer surgery, we think about the surgical process in two areas — the breast and the lymph nodes.

From the breast perspective, we often have two choices:

  • Lumpectomy – A procedure where we remove tissue just in the area where the cancer is located and leave the rest of the breast.
  • Mastectomy – A procedure where we remove the entire breast.

The choice between a lumpectomy and mastectomy rests in the hands of the patient and the surgeon and depends on a variety of factors, including but not limited to:

  • Size of the tumor relative to size of the breast
  • How the cancer presented
  • Subsequent risk of breast cancer in the remaining breast tissue
  • Whether or not radiation therapy is needed

Overall, it is a complex decision that requires a discussion between the patient and surgeon.

What should you know about a lumpectomy?

In most cases, lumpectomies are done on an outpatient basis, meaning the patient comes in for surgery in the morning and goes home in the afternoon. There will be scarring and some pain, but the pain is most often minor. The recovery time for a breast lumpectomy is also generally quick, with most patients recovering within a week or two of surgery.

Talk to a knowledgeable surgeon and, preferably, one who offers care at a multidisciplinary center and who works closely with a whole cancer team.

Dr. Emily Siegel, breast surgical oncologist at Keck Medicine of USC

What should you know about a mastectomy?

If you’re having a mastectomy or a double mastectomy — complete removal of one or both breasts, respectively — there are important options to keep in mind. Firstly, the length and complexity of surgery and recovery depends on whether breast reconstruction after a mastectomy is being done. With reconstruction, or remaking of the breasts by a plastic surgeon, the treatment timeline and recovery period can be longer. Whether or not to have breast reconstruction surgery following a mastectomy is another complex decision, which requires discussion between the cancer surgeon, patient and plastic surgeon.

If no breast reconstruction is being performed, breast cancer patients at USC Norris, part of Keck Medicine, come to the hospital the morning of the operation, stay overnight and are generally discharged the next morning.

What is lymph node surgery for breast cancer?

Switching focus to the lymph nodes — this type of surgical procedure is done so that the surgeon can determine whether the cancer has spread beyond the breast. Most often, the goal of the procedure is to determine if cancer cells have gotten into the lymphatic channels in the breast tissue and made their way to the lymph nodes, most often located in the axilla or armpit area.

To check if the cancer has spread, the surgeon starts by removing only the lymph node that would be most likely to have cancer, if any. This is called the sentinel lymph node, or the guardian of the rest of the nodes. We, as surgeons, need help finding this special lymph node because all lymph nodes look the same.

To locate the sentinel lymph node, we inject the patient’s breast with one or two substances, which travel to the lymph nodes the same way a cancer would. These substances are often, but not always, a blue dye or radioactive liquid. The substances travel to the lymph nodes, and those nodes that appear radioactive and/or blue are identified as the sentinel node(s). The nodes are removed and sent to the lab for analysis. The decision whether or not to remove the remaining lymph nodes — generally, two-thirds of the lymph nodes in the armpit are removed — requires a discussion between the patient and doctor to evaluate the complexities and potential benefits of surgery.

The importance of multidisciplinary care for breast cancer.

By and large, that’s the general breakdown of breast cancer surgery. The decision-making process is quite nuanced, and breast cancer treatment recommendations are always changing or getting updated. So, the final advice to keep in mind is this — talk to a knowledgeable surgeon and, preferably, one who offers care at a multidisciplinary center and who works closely with a whole cancer team, including medical oncologists, surgical oncologists and radiation oncologists.

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Emily Siegel, MD
Dr. Emily Siegel is a breast surgical oncologist at Keck Medicine of USC, who specializes in surgical treatment for breast cancer.