Reported breast cancer symptoms include:

• discharge from the nipple(clear or bloody)
• persistent tenderness of the breast
• pain in the nipple
• swelling or mass in the armpit (lymph nodes)
• inverted or scaly nipples
• a lump that can be felt, no matter how small
• swelling of the breast

Sometimes there are no symptoms of breast cancer when it is in the early stages. If you notice a lump, or are experiencing anything unusual, you must report the symptoms to your doctor as soon as possible. Performing a monthly self breast exam is the one of the best ways to notice any changes in your breasts.

More About Breast Cancer Symptoms

Risk factors

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Pathophysiology

Breast cancer is either invasive or noninvasive (often referred to as in situ).  There are two types of noninvasive breast cancers: ductal carcinoma in situ (DCIS) and lobular carcinoma in situ  (LCIS).  These two types of noninvasive breast cancers do not invade the basement membrane of the breast (see Fig. 1, Anatomy of the Breast).  As their names suggest ductal carcinoma in situ cancer cells are found in the lining of the duct whereas lobular carcinoma in situ cancer cells are found in the lobules (see Anatomy section for a detailed description of the ductals and lobules of the breast).

Breast cancer, like other cancers, occurs because of an interaction between the environment and a defective gene. Normal cells divide as many times as needed and stop. They attach to other cells and stay in place in tissues. Cells become cancerous when mutations destroy their ability to stop dividing, to attach to other cells and to stay where they belong. When cells divide, their DNA is normally copied with many mistakes.

 

Error-correcting proteins fix those mistakes. The mutations known to cause cancer, such as p53, BRCA1 and BRCA2, occur in the error-correcting mechanisms. These mutations are either inherited or acquired after birth. Presumably, they allow the other mutations, which allow uncontrolled division, lack of attachment, and metastasis to distant organs. Normal cells will commit cell suicide (apoptosis) when they are no longer needed. Until then, they are protected from cell suicide by several protein clusters and pathways.

One of the protective pathways is the PI3K/AKT pathway; another is the RAS/MEK/ERK pathway. Sometimes the genes along these protective pathways are mutated in a way that turns them permanently "on", rendering the cell incapable of committing suicide when it is no longer needed. This is one of the steps that causes cancer in combination with other mutations. Normally, the PTEN protein turns off the PI3K/AKT pathway when the cell is ready for cell suicide.

In some breast cancers, the gene for the PTEN protein is mutated, so the PI3K/AKT pathway is stuck in the "on" position, and the cancer cell does not commit suicide.

There are the two types of noninvasive  breast cancer described above and there are also two types of invasive breast cancer: infiltrating ductal carcinoma and infiltrating lobular carcinoma.  

As their names suggest, infiltrating ductal carcinoma penetrates the wall of the duct and travels to areas outside of it whereas infiltrating lobular carcinoma spreads through the wall of the lobule and also travels to areas outside of it.  Infiltrating ductal carcinoma is the most common type of breast cancer, accounting for between 70%-80% of the cases of breast cancer. 

Mutations that can lead to breast cancer have been experimentally linked to estrogen exposure.

Failure of immune surveillance, the removal of malignant cells throughout one's life by the immune system.

Abnormal growth factor signaling in the interaction between stromal cells and epithelial cells can facilitate malignant cell growth.In breast adipose tissue, overexpression of leptin leads to increased cell proliferation and cancer.

Breast cancer, like other forms of cancer, is the outcome of multiple environmental and hereditary factors. Some of these factors include:

1. Lesions to DNA such as genetic mutations. Mutations that can lead to breast cancer have been experimentally linked to estrogen exposure.
2. Failure of immune surveillance, a theory in which the immune system removes malignant cells throughout one's life.
3. Abnormal growth factor signaling in the interaction between stromal cells and epithelial cells can facilitate malignant cell growth.
4. Inherited defects in DNA repair genes, such as ''BRCA1'', ''BRCA2'' and ''TP53''. People in less-developed countries report lower incidence rates than in developed countries. 

breast cancer symptoms

 Initially, breast cancer may not cause any symptoms. A lump may be too small for you to feel or to cause any unusual changes you can notice on your own. Often, an abnormal area turns up on a screening mammogram (x-ray of the breast), which leads to further testing.

In some cases, however, the first sign of breast cancer is a new lump or mass in the breast that you or your doctor can feel. A lump that is painless, hard, and has uneven edges is more likely to be cancer. But sometimes cancers can be tender, soft, and rounded. So it's important to have anything unusual checked by your doctor.

Reported breast cancer symptoms include:

1. discharge from the nipple(clear or bloody)
2. persistent tenderness of the breast
3. pain in the nipple
4. swelling or mass in the armpit (lymph nodes)
5. inverted or scaly nipples
6. a lump that can be felt, no matter how small
7. swelling of all or part of the breast
8. skin irritation or dimpling
9. breast pain
10. the nipple turning inward
11. redness, scaliness, or thickening of the nipple or breast skin
12. a nipple discharge other than breast milk
13. a lump in the underarm are

Sometimes there are no symptoms of breast cancer when it is in the early stages. If you notice a lump, or are experiencing anything unusual, you must report the symptoms to your doctor as soon as possible. Performing a monthly self breast exam is the one of the best ways to notice any changes in your breasts.

Breast Cancer Evaluation

The evaluation of breast cancer begins with a medical history and physical examination.

Physical findings of breast cancer in someone with breast cancer may include:

• New breast lump
• Changes in breast shape or size
• Dimpling in the skin of the breast 
• New lump in the armpit that does not go away
• Nipple discharge from one breast
• Orange-peel color of the skin overlying the breast 
• Retracted (pointing inward) nipple or changes in the nipple 

For evaluation breast cancer a Testing is required to evaluate breast cancer.

Tests breast cancer that may be used to evaluate breast cancer include:

• Breast biopsy 
• Miraluma breast scan 
• Bone scan:
• To look for cancer that has spread
• Breast ultrasound:
• May help to identify breast swelling caused by a cyst.
• Sentinel node biopsy 
• Breast tissue hormone status
• Mammography:
• This is a special x-ray that can reveal close to 90% of all breast cancers

Breast Lump

Breast lamp changes are common. From the time a girl begins to develop breasts and begins menstruating and throughout life, women may experience various kinds of breast pain and other breast changes. Some of these changes normally occur during the menstrual cycle, during pregnancy, and with aging. Breast lumps, tenderness, and other changes may occur. 

Most breast lumps and other changes are not cancer.

Your breast is composed of several glands and ducts that lead to the nipple and the surrounding colored area called the areola.

The milk-carrying ducts extend from the nipple into the underlying breast tissue like the spokes of a wheel. Under the areola are lactiferous ducts.

These fill with milk during lactation after a woman has a baby. When a girl reaches puberty, changing levels of hormones cause the ducts to grow and cause fat deposits in the breast tissue to increase.

The glands that produce milk (mammary glands) that are connected to the surface of the breast by the lactiferous ducts may extend to the armpit area (axilla).

There are no muscles in the breasts, but muscles lie under each breast and cover the ribs. These normal structures inside the breasts can sometimes make them feel lumpy. Such lumpiness may be especially noticeable in women who are thin or who have small breasts.

1.  Breast pain is a common breast problem mostly in younger women who are still having their periods, and happens less often in older women. Although pain is a concern, breast pain is rarely the only symptom of breast cancer. Most breast cancers involve a mass or lump.
2. Breast pain or tenderness may also occur in a teenage boy. The condition, called        gynecomastia, is enlargement of the male breast which may occur as a normal part of development, often during puberty.
3. Lumps within breast tissue are usually found unexpectedly or during a routine monthly breast self-exam. Most lumps are not cancer but represent changes within the breast tissue. As your breasts develop, changes occur. These changes are influenced by normal hormonal variations.
4. Cyclic mastalgia: About two-thirds of women with breast pain have a problem called cyclic mastalgia. This pain typically is worse before your menstrual cycle and usually is relieved at the time your period begins. The pain may also happen in varying degrees throughout the cycle. Because of its relationship to the menstrual cycle, it is believed to be caused by hormonal changes. This type of breast pain usually happens in younger women, although the condition has been reported in postmenopausal women who take hormone replacement therapy.
5. Noncyclic mastalgia: Breast pain that is not associated with the menstrual cycle is called noncyclic mastalgia. It occurs less often than the cyclic form. It typically occurs in women older than 40 years and is not related to the menstrual cycle. It is sometimes linked to a fibrous mass (called a fibroadenoma) or a cyst.
6. Breast infection: The breast is made up of hundreds of tiny milk-producing sacs called alveoli. They are arranged in grapelike clusters throughout the breast. Once breastfeeding begins, milk is produced in the alveoli and secreted into tube-shaped milk ducts that empty through the nipple.
7. Mastitis is an infection of the tissue of the breast that occurs most frequently during the time of breastfeeding. This infection causes pain, swelling, redness, and increased temperature of the breast. It can occur when bacteria, often from the baby's mouth, enter a milk duct through a crack in the nipple. This causes an infection and painful inflammation of the breast.

History

 The oldest description of cancer was discovered in Egypt and dates back to approximately 1600 BC. The Edwin Smith Papyrus describes 8 cases of tumors or ulcers of the breast that were treated by cauterization

  breast cancer was the form of cancer most often described in ancient documents.Because autopsies were rare, cancers of the internal organs were essentially invisible to ancient medicine. Breast cancer, however, could be felt through the skin, and in its advanced state often developed into fungating lesions: the tumor would become necrotic (die from the inside, causing the tumor to appear to break up) and ulcerate through the skin, weeping fetid, dark fluid.

Although breast cancer was known in ancient times, it was uncommon until the 19th century, when improvements in sanitation and control of deadly infectious diseases resulted in dramatic increases in lifespan. Previously, most women had died too young to have developed breast cancer. Additionally, early and frequent childbearing and breastfeeding probably reduced the rate of breast cancer development in those women who did survive to middle age.

Mastectomy for breast cancer was performed at least as early as 548 CE, when it was proposed by the court physician Aetios of Amida to Theodora. It was not until doctors achieved greater understanding of the circulatory system in the 17th century that they could link breast cancer's spread to the lymph nodes in the armpit. The French surgeon Jean Louis Petit (1674–1750) and later the Scottish surgeon Benjamin Bell (1749–1806) were the first to remove the lymph nodes, breast tissue, and underlying chest muscle.

During the 1970s, a new understanding of metastasis led to perceiving cancer as a systemic illness as well as a localized one, and more sparing procedures were developed that proved equally effective. Modern chemotherapy developed after World War II.