This page was reviewed under our medical and editorial policy by
Daniel Liu, MD, Plastic and Reconstructive Surgeon
This page was reviewed on February 4, 2022.
A double mastectomy—also known as a bilateral mastectomy—is exactly what it sounds like: a surgery in which both breasts are removed at the same time.
It’s major surgery that removes both breasts to remove cancer, or to reduce the risk of breast cancer in a woman who may be at high risk for the disease. It usually requires a short hospital stay and a longer recovery time that may take a few weeks to several weeks, depending on the circumstances.
The two main types of mastectomy are:
A radical mastectomy, which involves not only removing the entire breast and lymph nodes, but also the pectoral muscles that are located under the breast, is rarely done these days, except in the case of larger tumors growing into the pectoral muscles. The American Cancer Society notes that a modified radical mastectomy has been found to be as effective with fewer side effects.
For those undergoing an immediate mastectomy, these options describe the pattern of skin incisions:
An oncologist carefully evaluates a double mastectomy as a treatment option by comparing it to the benefits and risks of other breast-conserving surgeries.
Many people with early-stage cancer can choose between breast-conserving surgery or mastectomy. Studies show that, for them, opting for mastectomy or breast-conserving surgery plus radiation therapy has similar outcomes. That can vary based on a number of reasons that are specific to a woman’s diagnosis and circumstances.
Breast reconstruction can be done at the same time as the mastectomy or at any later time. Many women also opt not to have reconstruction.
You will receive general anesthesia before your surgery, so you’ll be asleep during the procedure. Unless you’ve decided on a nipple-sparing surgery, the surgeon will remove as much of the tissue as possible from both your breasts. This includes the skin, nipple and areola.
Sometimes that also includes the lymph nodes from under the arm. The doctor may also remove part of the pectoral muscles, located under the breasts.
As part of the surgery, the surgeon will remove breast tissue and insert one or two tubes for fluid to drain into.
Sometimes breast reconstruction is performed at the same time as a mastectomy. Choices for reconstruction include breast reconstruction using breast implants or what’s known as tissue flap surgery, which reconstructs the breast by using muscle, fat and skin taken from other parts of the body.
At the end of the surgery, the area is closed with stitches.
A woman who has undergone a mastectomy typically stays in the hospital for one or two nights.
You can expect temporary soreness in your chest, underarm and shoulder, as well as possible numbness across your chest that may be permanent.
The surgical drains that were inserted inside your breast area during surgery typically stay in for about one week to 10 days.
While recovering from surgery, most people have some pain. Recovery times vary depending on the specifics of your double mastectomy.
You'll likely receive a written list of instructions about post-surgical care that includes:
The side effects you may experience after a double mastectomy depend a lot on how complex the surgery is.
You may have:
Your breasts will likely look different than they did before surgery, including having new scars or being a different size or shape.
If you have pain that persists over time and includes numbness, burning, tingling and/or itching, it could be related to postmastectomy pain syndrome, or PMPS.
Rashes aren’t a common side effect of double mastectomies, but some people may have skin irritation due to bandages, medical tape, dry skin or radiation therapy. If you notice a rash, inform your care team right away. In some cases, it may be a sign of cancer recurrence.
Some women may need additional treatment after a double mastectomy to further prevent cancer from coming back. Your surgeon will remove all the cancer cells known to be in a certain area, plus a margin of healthy tissue around them, but microscopic cancer cells may remain. Treatment after surgery is intended to kill any microscopic cancer cells so they cannot spread. Any additional treatment that’s given after the main breast cancer treatment is called adjuvant therapy.
Adjuvant treatment after a double mastectomy may include:
Chemotherapy or targeted therapy: If either chemotherapy or targeted therapy is recommended after surgery, it’s typically the first adjuvant therapy that’s given.
Hormone therapy: For women who have hormone receptor-positive breast cancer, hormone therapy may be recommended after a double mastectomy. Most of these drugs reduce estrogen levels or block estrogen from acting on breast cancer cells, which stops them from growing.
Radiation: Radiation may be recommended if your doctor suspects there may still be cancer in the lymph nodes, chest wall or nearby tissue after surgery. Or, it may be given to help reduce the chance of cancer recurring for other reasons. Radiation can typically be given before or after breast reconstruction surgery, if you choose to have it.
If breast cancer comes back, the treatment is often surgery to remove the new cancer followed by radiation, as long as you haven’t had radiation in that same area previously. Depending on the new tumor’s size, you may undergo chemotherapy or another systemic treatment to try to shrink it before surgery.
Prophylactic mastectomy (also known as risk-reducing surgery) is performed on women who don’t have breast cancer but who choose to have both breasts removed.
You might choose this option if your breast cancer risk is very high. According to the National Cancer Institute (NCI), double mastectomy lowers the risk of developing breast cancer by at least 90 percent for women with a strong family history and by about 95 percent for those with a particular disease-causing mutation in the BRCA1 or BRCA2 genes.
High-risk gene mutations include:
This risk can be discovered through genetic testing. The lifetime risk of breast cancer for the average American woman is 12 percent.
All people have BRCA1 and BRCA2 genes, but only some people have the gene mutations linked to a higher cancer risk. According to the NCI:
In addition to the BRCA1 and BRCA2 gene mutations, an abnormality called a high-penetrance mutation in one of several other genes may also put you at high risk of breast cancer.
Some other reasons to consider a prophylactic mastectomy:
A contralateral prophylactic mastectomy is the procedure when someone has cancer in one breast and opts to also remove the healthy breast.
You might choose this:
The benefit of having a contralateral prophylactic mastectomy is more likely for someone who has cancer and a higher genetic risk for cancer. The benefit is not as clear for those who don’t have those other risk factors.
A mastectomy is not considered an appropriate option for someone with average or slightly increased breast cancer risk because, like all surgeries, the procedure carries its own risks, including bleeding and infection at the surgery site.
Even a double mastectomy can’t remove all your breast cells, so some risk remains.
Another surgery that may reduce breast cancer risk for high-risk women is a bilateral prophylactic salpingo-oophorectomy. This involves removing both ovaries and fallopian tubes. According to the NCI, this procedure may reduce the risk of ovarian cancer by about 90 percent, while also reducing the risk of breast cancer by about 50 percent for women at very high risk. Removing the ovaries may reduce the amount of estrogen produced in a premenopausal woman. This may slow the growth of some breast cancers.
Other options for reducing breast cancer risk besides surgery can include intensive screening. This might mean starting mammography at an earlier age (30 years old is recommended for those at high risk) or undergoing tests in addition to mammography.
Some medicines may also help lower your risk. Some drugs that may reduce cancer risk include antiestrogens or aromatase inhibitors, such as tamoxifen, raloxifene and exemestane.
It’s not yet clear whether these drugs can be used to prevent breast cancer in women at very high risk. Tamoxifen may help lower risk of cancer in a second breast among BRCA1 and BRCA2 carriers who were previously diagnosed with cancer.
