Cancer can start any place in the body.
It starts when cells in the breast grow out of control and crowd out normal cells. These cells usually form a tumor that can often be seen on an x-ray or felt as a lump. The tumor is malignant (cancerous) if the cells can grow into (invade) surrounding tissues or spread (metastasize) to distant areas of the body.
Breast cancer occurs almost entirely in women, but men can get it too.
There are many types of breast cancer. Some are very rare.
Most breast cancers are invasive, or infiltrating. These cancers have broken through the walls of the glands or ducts where they originated and grown into surrounding tissue. The prognosis of invasive breast cancer is strongly influenced by the state of the disease—that is, the extent or spread of the cancer when it is first diagnosed. There are two main staging systems for cancer. The TNM classification of tumors uses information on tumor size and how far it has spread within the breast and to adjacent tissues (T), the extend of spread to the nearby lymph nodes (N), and the presence or absence of distant metastases (M).
Once the T, N, and M are determined, a stage of 0, I, II, III, or IV is assigned, with stage 0 being in situ, stage I being early stage invasive cancer, and stage IV being the most advanced disease.
Breast cancer typically produces no symptoms when the tumor is small and most easily treated. Therefore, it is very important for women to follow recommended screening guidelines for detecting breast cancer at an early stage. When breast cancer has grown to a size that can be felt, the most common physical sign is a painless lump. Sometimes it can spread to underarm lymph nodes and cause a lump or swelling, even before the original breast tumor is large enough to be felt. Less common signs and symptoms include breast pain or heaviness; persistent changes to the breast, such as swelling, thickening, or redness of the skin; and nipple abnormalities such as spontaneous discharge, erosion, or retraction.
The American Cancer Society works relentlessly to help save lives from breast cancer — and all cancers — by helping people stay well and get well, by finding cures, and by fighting back against the disease. The American Cancer Society helps women stay well by encouraging them to take steps to reduce their risk of breast cancer or detect it early. For women who are diagnosed with breast cancer, the Society provides the information, day-to-day help, and emotional support to guide them through every step of their experience and to help them get well.
They also provide:
Many factors known to increase the risk of breast cancer are not modifiable, such as age, family history, early menarche, and late menopause. Factors that are modifiable include postmenopausal obesity, use of combined estrogen and progestin menopausal hormones, alcohol consumption, and breastfeeding. Many breast cancer risk factors affect lifetime exposure of breast tissue to hormones. Hormones are thought to influence breast cancer risk by increasing cell proliferation, thereby increasing the likelihood of DNA damage, as well as promoting cancer growth. Although breast cancer risk accumulates throughout a woman’s life, research suggests that the time between menarche and first pregnancy may be particularly critical. Many established risk factors for breast cancer are specifically associated with ER+/luminal breast cancer; less is known about the risk factors for ER or basal-like breast cancers.
Strategies that may help reduce the risk of breast cancer include avoiding weight gain and obesity, engaging in regular physical activity, and minimizing alcohol intake. The increased risk of breast cancer associated with the use of combined menopausal hormone therapy should be considered when evaluating treatment options for menopausal symptoms. Women who choose to breastfeed for an extended period of time of one year or more may also lower their breast cancer risk. Treatment with tamoxifen or raloxifene can also reduce the risk of breast cancer among women at high risk.
Risk factors to consider include:
There are many ways to treat breast cancer, but the main types of treatment are local or systemic. Surgery and radiation are used to treat only the cancer. They do not affect the rest of the body. This is called local treatment. Chemo and hormone treatment drugs go through the whole body. They can reach cancer cells anywhere in the body. They are called systemic treatment. Doctors often use both local and systemic treatments to treat breast cancer.
The treatment plan that’s best for you will depend on:
Possible treatments include: