Breast Cancer Treatment

About Breast Cancer

Making the right diagnosis is a critical component of successful cancer treatment. Penn's cancer specialists have wide-ranging experience treating all forms of breast cancer, including those that occur only rarely. Their expert understanding of the disease allows them to create cancer treatment plans that are customized for every patient.

Breast cancer, the uncontrolled growth of cells in the breast, is the most common type of cancer among women, excluding skin cancer. Breast cancer forms in the tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

Read more About Breast Cancer Treatment at Penn Medicine

Breast Cancer Diagnosis


Read more Breast Cancer Diagnosis

Breast Cancer Treatment

Breast Cancer Surgery options include breast-conserving surgery such as lumpectomy and partial mastectomy; total mastectomy; modified radical mastectomy; and radical mastectomy.

Two types of breast reconstructive surgery are offered at Penn: natural tissue reconstruction and breast implant reconstruction.

Radiation therapy options include accelerated partial breast irradiation (APBI), which includes breast brachytherapy and external beam partial breast irradiation; 3-D conformal radiation therapy; image-guided radiation therapy (IGRT); intensity-modulated radiation therapy (IMRT); targeted radiation therapy treatment called MammoSite®; internal mammary node irradiation; and prone breast radiotherapy.

Chemotherapy and biologic therapies for breast cancer include chemotherapy, hormone therapy, immunotherapy, and vaccine therapy.

Breast cancer clinical trials are also available at Penn.

Breast Cancer Surgery

Breast surgeons at Penn Medicine deal almost exclusively with breast cancer and disorders of the breast. They have popularized the concepts of breast conserving therapy and are pioneering the use of vaccines and immune-based therapies for the treatment of breast cancer. Penn is also a leader in the use of oncoplastic surgery, using techniques to remove the tumor and preserve or restore the breast's shape or appearance at the same time.

By constantly working to better understand the molecular characteristics of breast cancer, Penn's surgeons help develop new therapeutic options for treatment. Both independently and as part of the Abramson Cancer Center and the Abramson Cancer Center at Pennsylvania Hospital, Penn's breast surgeons have been involved with research endeavors that have changed the national standards with regard to the management of breast cancer

Surgery is also used to check the lymph nodes under the arm for cancer spread. Penn breast surgeons have a great deal of experience performing sentinel lymph node biopsy and an axillary (armpit) lymph node dissection.

Breast reconstruction can be done at the same time as the mastectomy or done later. Penn's plastic surgeons are leaders in the field of reconstructive surgery, including reconstructive microsurgery to improve appearance and function.

Breast-conserving Surgery

Breast-conserving surgery removes only the part of the breast affected by cancer and a surrounding margin of normal tissue. How much tissue is removed depends on the size and location of the tumor and other factors. Penn surgeons are leaders in the use of oncoplastic surgery, which uses techniques to remove the tumor and preserve or restore the breast's shape or appearance at the same time, such as skin-sparing mastectomy, and nipple sparring mastectomy.

Partial mastectomy, quadrantectomy and lumpectomy are all types of breast-conserving surgery. If cancer cells are found at any of the edges of the tissue removed, it is said to have positive margins. When no cancer cells are found at the edges of the tissue, it is said to have negative or clear margins. The presence of positive margins means that that some cancer cells may have been left behind after surgery. If the pathologist finds positive margins in the tissue removed by breast-conserving surgery, the surgeon may need to go back and remove more tissue. If the surgeon can't remove enough breast tissue to get clear surgical margins, a total mastectomy may be needed.

Radiation therapy is often given after surgery and small metallic clips (visible on X-rays) may be placed inside the breast during surgery to mark the area for the radiation treatments.


Mastectomy involves removing all of the breast tissue, sometimes along with other nearby tissues. In a simple or total mastectomy, the surgeon removes the entire breast, including the nipple, but does not remove underarm lymph nodes or muscle tissue from beneath the breast.

A modified radical mastectomy is a simple mastectomy plus removal of axillary (underarm) lymph nodes.

A radical mastectomy is an extensive operation where the surgeon removes the entire breast, axillary lymph nodes, and the pectoral (chest wall) muscles under the breast. This surgery was once very common, but a modified radical mastectomy has proven to be just as effective without the disfigurement and side effects of a radical mastectomy. Radical mastectomy may still be done for large tumors that are growing into the pectoral muscles under the breast.

For some women considering immediate breast reconstruction, a skin-sparing mastectomy can be done. Selected patients with small breasts and small, favorable, peripherally located tumors, or patients with small breasts undergoing prophylactic mastectomy, nipple-sparing mastectomy with immediate reconstruction is a cosmetically excellent option.

Choosing Between Lumpectomy and Mastectomy

Many women with early-stage cancers can choose between breast-conserving surgery and mastectomy. A small number of women having breast-conserving surgery may not need radiation while a small percentage of women who have a mastectomy will still need radiation therapy to the breast area.

Chemotherapy may be given before the surgery to shrink the tumor and reduce the amount of tissue that needs to be removed during surgery. Chemotherapy treatment given before surgery is called neoadjuvant therapy.

Even if the doctor removes all the cancer that can be seen at the time of the surgery, some patients may still need radiation therapy, chemotherapy, or hormone therapy after surgery to kill any cancer cells that are left. Treatment given after the surgery to lower the risk of the cancer coming back is called adjuvant therapy.

Breast Reconstructive Surgery

Breast reconstruction is a surgical procedure to recreate the shape and appearance of the breast, usually done as part of a mastectomy, surgery to remove an entire breast as treatment for breast cancer.

There are two types of breast reconstruction:

Most insurance providers cover the cost of breast reconstruction after mastectomy.

Penn plastic surgeons are highly skilled and perform the most sophisticated types of breast reconstruction on a daily basis. They provide patients with options for breast reconstruction and work with the surgical, medical, and radiation oncologists in providing the safest and most appropriate surgical plan to restore the body and to help patients heal.

Many women consult with a Penn reconstructive plastic surgeon soon after being diagnosed with breast cancer. This allows plastic surgery to be an integral part of the cancer treatment team.

Women who previously had a mastectomy may still be able to restore a more natural appearance. They should speak with a Penn plastic surgeon about reconstructive surgery to determine their options.


Most surgeons agree that the aesthetic result and technical ease are improved in an immediate breast reconstruction compared to delayed reconstruction. Surgeons at Penn Medicine typically utilize skin-sparing mastectomies (SSM). This method of mastectomy allows for satisfactory local control of the breast cancer while preserving the breast boundaries. When breast reconstruction is performed in the immediate setting, there is no scar tissue to overcome and the skin envelope helps maintain the natural borders of the breast. By preserving the natural skin brassiere, the reconstruction is more straightforward and leads to a reconstruction that is more symmetric to the opposite breast.

Natural Tissue Reconstruction

In natural tissue reconstruction, Penn plastic surgeons move tissue from the belly or back of the patient to the breast. Though this surgery is more extensive, it can provide a great emotional benefit and is often performed during the same operation as the mastectomy.

The best option is an autologous tissue reconstruction using tissue from the patient's lower abdomen. The moved tissue is kept alive on a muscle or microsurgery can be used to reattach blood vessels to keep the transplanted tissue alive. Patients can expect to spend four to five days in the hospital for natural tissue reconstruction.

Patients desiring autologous tissue reconstruction from the abdomen must have sufficient lower abdominal tissue available to reconstruct the breast. If the lower abdomen is not a sufficient donor site, or if previous surgery eliminates the potential use of this tissue, a number of alternative flaps from other parts of the body have been developed as additional options.

Penn plastic surgeons are among the most skilled in the country in performing autologous breast reconstruction. As in all procedures, there are complications associated with autologous breast reconstruction, including total flap failure or partial flap failure. Total flap failure is a rare complication occurring in less than 1 percent of Penn patients.

Breast Implant Reconstruction

Not every woman has the option of using her own tissue. In those cases, breast implants or tissue expanders are used in breast reconstruction. Saline and silicone implants are quite safe and present unique benefits to cancer patients. As a leader in breast reconstruction, Penn is participating in a national study analyzing the use of silicone breast implants in breast reconstruction.

For many women who chose implant reconstruction, tissue expanders are initially placed underneath the muscles of the chest. The expanders undergo several inflations using saline to create a sizable'pocket' for the subsequent implant. Once the appropriate'pocket' has been achieved, the patient returns to the operating room for removal of the tissue expander in exchange for a silicone or saline implant. Both types of implants are available, and to date, no study has documented a cause and effect relationship between silicone or saline implants and systemic illness.


The principle benefit of using implants for breast reconstruction is in the ease of reconstruction and limiting the surgical site to the chest. Implant reconstruction does, however, have both aesthetic and functional downsides. The implant can be felt and is often visible through the breast skin. An implant reconstruction is also less natural in shape and consistency when compared to a natural breast.

Patients can expect to stay in the hospital one to two nights after breast implant reconstructive surgery. Women who have been given tissue expanders or breast implants most often experience discomfort for about a week. They can also expect two or three days of tenderness after each expansion.

Women who have had their own tissue used in the reconstruction can expect to have discomfort around their breasts and where the tissue was removed for two to three weeks.

Reconstructive surgery has risks, but patients can help prevent complications by carefully following their physician's instructions both before and after surgery and understanding the potential risks and complications. Infection is the most common postoperative implant-related complication.

Restoration of the breast following mastectomy has become an integral part of the holistic treatment of breast cancer. Reconstruction of the breast can happen at the time of mastectomy or at a later date as a separate operation depending on a variety of factors. These may include the women's wishes, desires and goals, the type and size of tumor, the possible need for post-operative radiation therapy or chemotherapy. The surgeon, oncologist, and plastic surgeon all assist the patient in making this decision.

The overall goals of breast reconstruction are to achieve a normal and symmetric silhouette, to limit patient morbidity, and to avoid the need for an external prosthesis.

Radiation Therapy for Breast Cancer

Penn Radiation Oncology has an international reputation for developing alternatives to mastectomy in the treatment of early stage breast cancer. Penn radiation oncologists were pioneers in providing radiation therapy following lumpectomy as an alternative to mastectomy. They work side-by-side with their surgical and medical colleagues to conduct pilot studies of locally advanced breast cancer.

Radiation therapy is used to destroy any microscopic cancer cells that may still be present in the breast/chest wall or regional lymph nodes following complete surgical removal of all visible cancer. Radiation is almost always recommended after lumpectomy and may also be advised after mastectomy for some women.

Penn radiation oncologists are experts in using multiple advanced radiation techniques to treat all tissues at risk of harboring residual microscopic breast cancer cells after surgery while minimizing exposure to the adjacent normal tissues such as the heart and the lung, thereby minimizing the risks of short and long-term side effects from radiation therapy.

Accelerated Partial Breast Irradiation (APBI)

Patients who have been diagnosed with an early-stage breast cancer (stage 0, I or II), with limited or no lymph node involvement, and a tumor size smaller than 3 cm (about the size of a walnut), may be eligible to receive a treatment option called APBI. APBI can be delivered using either brachytherapy or external beam radiation delivered by a linear accelerator.

For brachytherapy, a catheter is placed into the lumpectomy cavity by the patient's breast surgeon. The radiation is then delivered by temporary insertion of a radioactive source into the catheter, generally twice a day for one week. There are a number of catheters from different manufacturers that can be used to help deliver breast brachytherapy. Two of the more commonly used devices are the MammoSite® and MammoSite® ML catheters.

Conformal Radiation Therapy

The imaging technology used by radiation oncologists at Penn Medicine can be used to shape the radiation treatment beam to the shape of the region at risk of harboring microscopic cancer cells. Known as conformal radiation therapy, this technology gives doctors more control to treat the tissues that may contain cancer cells while avoiding the healthy normal tissues as much as possible.

In conformal radiation, a special computer uses CT imaging scans to create 3-D maps of the region being targeted for treatment (breast or chest wall and, in some cases, the regional lymph node areas). The system permits delivery of radiation from several directions and the beams can then be shaped, or conformed, to match the shape of the target volume. Conformal radiation therapy limits radiation exposure to nearby healthy tissue as well as the tissue in the beam's path.

Image-guided Radiation Therapy (IGRT)

In image-guided radiation therapy (IGRT), the linear accelerators that deliver radiation are equipped with imaging technology that take pictures of the region being treated immediately before or even during the time radiation is delivered. The purpose of IGRT is to ensure accurate delivery of the radiation therapy on a daily basis.

Specialized computer software is used to compare these images taken prior to treatment to images taken during the CT-simulation to establish that the patient is in the correct treatment position. Necessary adjustments can then be made to the patient's position and/or the radiation beams to more precisely target radiation at the breast cancer and avoid the healthy surrounding tissue.

Imaging used in IGRT includes:

  • Computed tomography (CT)
  • Magnetic resonance imaging (MRI)
  • Positron emission tomography (PET)
  • X-rays

Intensity-modulated Radiation Therapy (IMRT)

Intensity-modulated radiation therapy (IMRT) is used to improve the evenness of the radiation dose distribution with the breast, allowing women to complete their course of radiation therapy with less skin irritation compared with conventional radiation techniques. The even radiation dose distribution achieved by IMRT may also improve the long-term appearance of the irradiated breast.


MammoSite is a targeted radiation therapy treatment in which a small, soft balloon attached to a thin catheter is placed inside the lumpectomy cavity through a small incision in the breast. During therapy, the portion of the catheter that remains outside of the breast is connected to a computer-controlled high-dose rate machine that inserts a radiation"seed" to deliver the therapy to the area where cancer is most likely to recur.

Once the therapy is complete, the seed is removed and the catheter unplugged.

Chemotherapy and Biologic Therapies for Breast Cancer

Penn medical oncologists are experts in treating breast cancer with chemotherapy and other approaches, including hormonal therapy. They lead the way in developing new targeted therapies such as the use of monoclonal antibodies, vaccines and immune-based therapies. The Abramson Cancer Center's NCI-funded and approved breast cancer research program and active clinical trials group have pioneered some of the standard treatments used around the world to treat breast cancer.

Many cancer treatments are used in combination to lower the risk that the cancer will come back. Adjuvant therapy, treatment given after surgery, may include chemotherapy, radiation, hormone therapy, targeted therapy, immunotherapy or vaccine therapy.


Penn medical oncologists have a great deal of experience in the use of chemotherapy as part of an overall breast cancer treatment program and in chemotherapy research. Chemotherapy uses drugs to kill cancer cells.

Hormone Therapy

Hormone therapy is another form of breast cancer treatment. It is most often used as adjuvant therapy to help reduce the risk of cancer recurrence after surgery. It is also used to treat cancer that has come back after treatment or has spread. Estrogen promotes the growth of about two out of three breast cancers – those containing estrogen receptors (ER-positive cancers) and/or progesterone receptors (PR-positive cancers). Because of this, several approaches to blocking the effect of estrogen or lowering estrogen levels are used to treat ER-positive and PR-positive breast cancers. Hormone therapy does not help patients whose tumors are both ER- and PR-negative.


Immunotherapy is designed to repair, stimulate, or enhance the immune system's response to breast cancer cells. Penn medical oncologists are experts in the use of immunotherapy to stimulate the immune system to work harder, recognizing the difference between healthy cells and breast cancer cells, and eliminating the cancer cells.

Vaccine Therapy

Cancer vaccines are designed to teach the immune system to attack and destroy cancer cells. Normally, when foreign cells such as a bacterial infection enter the body, the immune system responds to the invasion and clears the body of the foreign cells. Unlike infectious cells, cancer cells are not recognized as foreign by the body. Instead, the immune system thinks the cancer cells are part of the normal body and do not mount an immune response against the cancer. Cancer vaccines allow the immune system to recognize cancer cells as foreign and, therefore, trigger the immune system to attack the cancer cells.

Breast Cancer Survivorship

There are more than 12 million cancer survivors living and thriving today as a result of advances in cancer treatment. However, cancer treatments can result in physical, emotional and financial complications long after the therapy is complete. Survivorship programs at Penn Medicine are a distinct phase of breast cancer care and are designed to help patients' transition from their cancer treatment routine to a post-cancer care lifestyle.

Read more Breast Cancer Survivorship

Tanya Zekovitch


Clinical Trials

Breast Cancer Trials
