Excluding skin cancer, breast cancer is the most common cancer among U.S. women, accounting for one in three cancers diagnosed in women. Thanks to dramatic improvements in research, breast cancer screening, treatment and early detection, millions of women are surviving breast cancer today. Whether you’re concerned about developing breast cancer, making decisions about treatment, or trying to stay well after treatment, we are here to help.
Breast cancer terminology and types:
Cancer that begins in the lining layer (epithelial cells) of organs like the breast. Nearly all breast cancers are carcinomas (either ductal carcinoma or lobular carcinoma).
Carcinoma that starts in glandular tissue (in the breast, tissue that makes and secretes milk). The ducts and lobules of the breast are glandular tissues, so cancers starting in these areas are often called adenocarcinomas.
CARCINOMA IN SITU
The term for the earliest stage of cancer (Stage 0), when it is confined to the layer of cells where it began and has not invaded deeper into breast tissues or into other parts of the body. This type of breast cancer is called ductal carcinoma in situ or DCIS, also referred to as non-invasive or pre-invasive breast cancer because it could become invasive if left untreated. Cancer that’s confined to the lobules is called lobular carcinoma in situ and is not a true cancer or pre-cancer — however, it may signal an increased risk of developing breast cancer.
INVASIVE OR INFILTRATING CARCINOMA
An invasive cancer is one that has already grown beyond the layer of cells where it started, infiltrating surrounding tissues and sometimes into the lymph nodes.
This is the most common type of breast cancer. Invasive (or infiltrating) ductal carcinoma (IDC) starts in a milk duct of the breast, breaks through the wall of the duct, and grows into the fatty tissue of the breast. From there, it could spread (metastasize) to other parts of the body through the lymphatic system and bloodstream. About 8 of 10 invasive breast cancers are infiltrating ductal carcinomas. Invasive lobular carcinoma (ILC) starts in the milk-producing glands (lobules) and can spread to other parts of the body. About one invasive breast cancer in 10 is an ILC. Invasive lobular carcinoma may be harder to detect by a mammogram than invasive ductal carcinoma.
INFLAMMATORY BREAST CANCER (IBC)
This uncommon type of invasive breast cancer usually does not grow as a single lump or tumor, but rather makes the skin on the breast look red and feel warm. The skin may also have a thick, pitted “orange peel” appearance. In its early stages, IBC is often mistaken for an infection in the breast (mastitis). Because there is no lump, IBC might not show up on a mammogram, which can make it harder to find early.
TRIPLE-NEGATIVE BREAST CANCER
These breast cancers (usually IDC) have cells that lack estrogen receptors and progesterone receptors and do not have excess HER2 protein on cell surfaces. This form of breast cancer can occur in younger women and African-American women. Triple-negative breast cancers tend to grow and spread quickly. Hormone therapy and drugs targeting HER2 are not effective treatments, but chemotherapy can be, and is often recommended as it lowers the risk of the cancer reoccurring.
PAGET DISEASE OF THE NIPPLE
This rare breast cancer starts in the breast ducts and spreads to the skin of the nipple and then to the areola, the dark circle around the nipple. The skin may become crusted, scaly and red, with bleeding or oozing and a burning or itching sensation. Paget disease is almost always associated with either DCIS or IDC.
Everyone should know the symptoms and signs of breast cancer and perform monthly breast self-exams. If you notice changes in your breast, make an appointment with your healthcare professional right away.
A CHANGE IN HOW THE BREAST OR NIPPLE FEELS
- Nipple tenderness or a lump or thickening in or near the breast or underarm area
- Change in the skin texture or an enlargement of pores in the skin (orange peel texture)
- A lump in the breast (all lumps should be investigated by a healthcare professional, but not all lumps are cancerous)
A CHANGE IN HOW THE BREAST OR NIPPLE LOOKS
- Any unexplained change in the size or shape of the breast
- Dimpling anywhere on the breast
- Unexplained swelling of the breast (especially if on one side only)
- Unexplained shrinkage of the breast (especially if on one side only)
- Recent asymmetry of the breasts (it is common to have one breast that is slightly larger than the other, but if the onset of asymmetry is recent, it should be checked)
- Nipple that is turned slightly inward or inverted
- Skin of the breast, areola, or nipple that becomes scaly, red, or swollen or has ridges or pitting resembling the skin of an orange
ANY NIPPLE DISCHARGE—PARTICULARLY CLEAR DISCHARGE OR BLOODY
A milky discharge that is present when a woman is not breastfeeding should be checked by her doctor, although it is not linked with breast cancer.
Today, there are many approaches to treating breast cancer. Your medical team will develop a treatment plan best suited for you based on your tumor’s stage of development, location, size and type of cancer. Your plan may include one form of therapy or a powerful combination of treatments that are tailored specifically to you. Treatments can be classified into broad groups, based on how they work and when they are used.
Patients who have no detectable cancer after surgery are often given additional treatment to help keep the cancer from coming back with breast cancer screening. This is known as adjuvant therapy. Even in the early stages of breast cancer, cancer cells may break away from the primary breast tumor and begin to spread into the lymphatic system and/or bloodstream. The goal of adjuvant therapy is to kill these hidden cells. Both systemic therapy (like chemotherapy, hormone therapy, and targeted therapy) and radiation can be used as adjuvant therapy.
This is treatment, such as chemotherapy or hormone therapy, given before surgery to shrink the tumor so that surgery can be less extensive. Many patients who get neoadjuvant therapy will not need adjuvant therapy, or will not need as much.
Surgical removal of the breast tumor is usually the first step in treatment and can range from excision of the tumor and a small amount of surrounding tissue (lumpectomy) to the complete removal of the breast tissue, adjacent lymph nodes and some of the underlying chest muscle (modified radical mastectomy). The extent of the surgery depends on the type of cancer, how far it has spread, and your specific genetic risks for recurrence.
High intensity x-rays and other types of radiation can kill cancer cells or stop their growth. External radiation therapy targets the cancer from outside the body. Internal radiation therapy places a radioactive substance directly into or near the cancer. Today’s radiation treatments are very precisely focused, minimizing their effect on the surrounding skin or healthy tissues.
- Accelerated Partial-breast Irradiation (APBI)
This new, proven treatment delivers radiation from inside the lumpectomy cavity (the space left after the tumor is removed) directly to the tissue surrounding the cavity where the cancer is most likely to recur.
- Intensity-modulated radiation therapy (IMRT)
IMRT’s computerized precision helps your radiation oncologist deliver a very even dose of radiation to the breast, preventing “hot spots” where some areas receive more radiation than others. This helps minimize side effects.
- Image-guided radiation therapy (IGRT)
Image-guided radiation therapy (IGRT), also called stereotactic radiosurgery, delivers extremely high doses of radiation to a very tightly circumscribed area.
Chemotherapy (chemo) is treatment with cancer-killing drugs that may be given intravenously (injected into a vein) or by mouth. The drugs travel through the bloodstream to reach cancer cells in most parts of the body. Chemo is given in cycles, with each period of treatment followed by a recovery period. Treatment usually lasts for several months. Chemo can also be used as the main treatment for women whose breast cancer has advanced beyond the breast and underarm area. The length of treatment depends on whether the cancer shrinks, how much it shrinks, and how a woman tolerates treatment.
Hormone therapy is most often used as an adjuvant therapy to help reduce the risk of the cancer coming back after surgery, but it can also be used as neoadjuvant treatment. It is also used to treat cancer that has come back after treatment or has spread — about 2 out of 3 breast cancers are hormone receptor-positive. Most types of hormone therapy for breast cancer either stop estrogen from acting on breast cancer cells or lower estrogen levels.
Targeted therapy drugs such as trastuzumab and lapatinib (Tykerb) may be used with other chemo drugs for tumors that are HER2-positive. As researchers have learned more about the gene changes in cells that cause cancer, they have been able to develop newer drugs that specifically target these changes. Targeted drugs work differently from standard chemotherapy (chemo) drugs. They often have different (and less severe) side effects.
When breast cancer spreads to bones, it can cause pain and lead to bone fractures and other problems. Drugs like bisphosphonates and denosumab can lower the risk of these problems and are also used to treat osteoporosis. Bisphosphonates such as Aredia® and Zometa® are given intravenously (IV). Denosumab (Xgeva®, Prolia®) is a newer drug that works differently from bisphosphonates and can be effective even after bisphosphonates stop working. Denosumabis injected under the skin every 4 weeks.
Research into the causes, prevention, and treatment of breast cancer is being done in many medical centers throughout the world. Research physicians, scientists and institutions continue work on:
CAUSES OF BREAST CANCER
Lifestyle Studies continue to uncover lifestyle factors and habits that alter breast cancer risk. Ongoing studies are looking at the effect of exercise, weight gain or loss, and diet on breast cancer risk.
Genetic testing Studies on the best use of genetic testing for BRCA1 and BRCA2 mutations continue at a rapid pace. Scientists are also exploring how common gene variations may affect breast cancer risk. Each gene variant has only a modest effect in risk (10 to 20%), but when taken together they may potentially have a large impact.
Environment Potential causes of breast cancer in the environment have also received more attention in recent years. While much of the science on this topic is still in its earliest stages, this is an area of active research.
The Sister Study is a large, long-term study designed to help find the causes of breast cancer. The studio is following 50,000 women who have sisters with breast cancer, collecting information about genes, lifestyle, and environmental factors that may cause breast cancer. To find out more about these studies, call 1-877-4-SISTER (1-877-474-7837) or visit the Sister Study Website (www.sisterstudy.org).
Chemoprevention Fenretinide, a retinoid, is being studied as a way to reduce the risk of breast cancer (retinoids are drugs related to vitamin A). In a small study, this drug reduced breast cancer risk as much as tamoxifen. Other drugs, such as aromatase inhibitors, are also being studied for risk reduction potential.
Making decisions about DCIS In some women, DCIS turns into invasive breast cancer, while in other cases the cells remain localized and do not become life-threatening. The uncertainty about how DCIS will behave makes it difficult for women to make decisions about what treatment to have. Researchers are studying statistical methods to estimate the odds that DCIS will become invasive.
NEW LABORATORY TESTS
Circulating tumor cells Researchers have found that breast cancer cells may break away from the tumor and enter the blood. These circulating tumor cells can now be detected with sensitive lab tests.
NEW IMAGING TESTS
Scintimammography (molecular breast imaging) In this technique, a low-level radioactive tracer is injected into a vein. The tracer attaches to breast cancer cells and is detected by a special camera. Current research is aimed at improving the technology and evaluating its efficacy.
Tomosynthesis (3-D mammography) During one session, the imaging machine takes many low-dose x-rays as it moves over the breast. The images are combined into a 3-dimensional picture, which may allow clearer views of problem areas and possibly find more cancers.
Oncoplastic surgery This surgical technique combines cancer-removal surgery and plastic surgery and typically involves reshaping the breast at the same time as the initial surgery. It may be necessary to operate on the healthy breast as well to make both breasts more symmetrical.
New chemotherapy drugs A newly-developed drug class called PARP inhibitors has shown promise in clinical trials treating breast, ovarian, and prostate cancers that have spread and are resistant to other treatments. Further studies are being done to see if this drug can help patients without BRCA mutations.
Targeted therapies This is a group of newer drugs that specifically take advantage of gene changes in cells that cause cancer.These drugs include those that target HER2 (Herceptin, Perjeta, Kadcyla Tykerb), anti-angiogenesis drugs that repress the growth of blood vessels that feed the tumor (Avastin), and drugs that help hormone therapy drugs work better (Afinitor).
Vitamin D A recent study found that women with early-stage breast cancer who were vitamin D deficient were more likely to have their cancer spread and had a poorer outlook. More research is needed to confirm this finding.