Breast Cancer Symptoms Signs

In the US, breast cancer is the third most common cause of cancer death (after lung cancer and colon cancer). In 2007, breast cancer is expected to cause 40,910 deaths (7% of cancer deaths; almost 2% of all deaths) in the U.S.

Among women in the U.S., breast cancer is the most common cancer and the second most common cause of cancer death (after lung cancer). Women in the U.S. have 1 in 8 lifetime chance of developing invasive breast cancer and a 1 in 33 chance of breast cancer causing their death.

The number of cases has significantly increased since the 1970s, a phenomenon partly blamed on modern lifestyles in the Western world. Because the breast is composed of identical tissues in males and females, breast cancer also occurs in males, though it is less common

- Ductal carcinoma 65-90%
- Lobular carcinoma 10%
- Inflammatory breast cancer
- Medullary carcinoma 5%
- Colloid carcinoma 2%
- Papillary carcinoma 1%
- Metaplastic carcinoma

It is important to have a model of causation of a disease in order to distinguish epidemiological risk factors or associations with disease, from the biological etiology and primary cause, secondary co-factors, and simple promoters of the disease. The first work on breast cancer epidemiology was done by Janet Lane-Claypon, who published a comparative study in 1926 of 500 breast cancer cases and 500 control patients of the same background and lifestyle for the British Ministry of Health.

Today, breast cancer, like other forms of cancer, is considered to be a result of damage to DNA. How this mechanism may occur comes from several known or hypothesized factors (such as exposure to ionizing radiation, or viral mutagenesis). Some factors lead to an increased rate of mutation (exposure to estrogens) and decreased repair (the BRCA1, BRCA2 and p53) genes. Although many epidemiological risk factors, and biological co-factors and promoters have been identified, the majority of breast cancer incidence remains unattributable, and the primary cause is unknown.

Dietary influences have been proposed and examined, and recent research suggests that low fat diets may significantly decrease the risk of breast cancer as well as the recurrence of breast cancer.A significant environmental effect was revealed by the large difference in breast cancer incidence between countries and continents, and a migration effect which slowly increases the risk of breast cancer even across generations after migration from a country of lower incidence to a country of higher incidence, such as moving from China or Japan to the United States. Humans are not the only mammal prone to breast cancer. Some strains of mice, namely the house mouse (Mus domesticus) are prone to breast cancer which is caused by infection with the mouse mammary tumour virus (MMTV or "Bittner virus" for its discoverer Hans Bittner), by random insertional mutagenesis. Suspicion of MMTV or other viruses in human breast cancer is controversial, and the idea is not generally accepted for lack of direct and definitive evidence. There is much more research in diagnosis and treatment of breast cancer than in its cause.

Age

The risk of getting breast cancer increases with age. For someone who lives to the age of 90, the chances of getting breast cancer is about 14.3% or one in seven during their lifetime. Men can also develop breast cancer, but their risk is less than one in 1000 (see sex and illnessThis risk is modified by many different factors. In 5% of breast cancer cases, there is a strong inherited familial risk.

Alcohol

Alcohol generally appears to increase the risk of breast cancer. The UK's Review of Alcohol: Association with Breast Cancer concludes that "studies confirm previous observations that there appears to be an association between alcohol intake and increased risk of breast cancer in women. On balance, there was a weak association between the amount of alcohol consumed and the relative risk.

Environmental causes

Women who have received high-dose ionizing radiation to the chest have a relative risk of breast cancer between 2.1 to 4.0. Most studies have not found an increased risk of breast cancer from active tobacco smoking, although a number of studies suggest an increased risk of breast cancer in both active smokers and those exposed to secondhand smoke compared to women who reported no exposure to secondhand smoke

Genes

Two autosomal dominant genes, BRCA1 and BRCA2, have been linked to the rare familial form of breast cancer. People in families expressing mutations in these genes have a 60% to 80% risk of developing breast cancer according to Robbins Pathological Basis of Disease.

Hormones

Persistently increased blood levels of estrogen are associated with an increased risk of breast cancer, as are increased levels of the androgens androstenedione and testosterone (which can be directly converted by aromatase to the estrogens estrone and estradiol, respectively).

Light levels

Researchers at the National Cancer Institute and National Institute of Environmental Health Sciences have concluded a study that suggests that artificial light during the night can be a factor for breast cancer.

Obesity

Gaining weight after menopause can increase a woman's risk. A recent study found that putting on 9.9kg (22lbs) after menopause increased the risk of developing breast cancer by 18%

* Lumps
* Rash
* Breast Pain
* Cysts
* Nipple Discharge
* Inverted Nipple

Breast cancer symptoms vary widely-from lumps to swelling to skin changes-and many breast cancers have no obvious symptoms at all. Symptoms that are similar to those of breast cancer may be the result of non-cancerous conditions like infection or a cyst.

Breast self-exam should be part of your monthly health care routine, and you should visit your doctor if you experience breast changes. If you're over 40 or at a high risk for the disease, you should also have an annual mammogram and physical exam by a doctor. The earlier breast cancer is found and diagnosed, the better your chances of beating it.