Breast cancer starts much the same as other cancers: a cell begins to grow and divide without normal controls, forming a mass of tissue called tumor. Most of the time, tumors are benign , and the non-life threatening cells do not spread. But when the tumor is malignant, it can spread to other parts of the body, and can be life threatening. When that malignancy starts within the breast, it is called breast cancer.
Though it primarily strikes women, breast cancer knows no boundaries as far as age, race, gender, or socio-economic status. It is the most commonly diagnosed cancer among women worldwide.
Causes of Breast Cancer
“We don’t know exactly what causes breast cancer,” says Susan Brown, MS, RN, director of health education for Susan G. Komen for the Cure. “But the many risk factors unique to women, such as estrogen levels and reproductive factors, may explain why it is so prevalent among women.”
Types of Breast Cancers
There are 2 primary types of breast cancers: invasive and ductal carcinoma in situ (DCIS). Invasive breast cancer develops when cancerous cells leave the milk duct, invade breast tissue and have the ability to spread to other parts of the body. This form of the disease is far more common than DCIS, and more difficult to treat.
Considered the earliest stage of breast cancer, and pre-invasive, DCIS occurs when abnormal cells grow in and are confined to the milk ducts. More than 62,000 women will be diagnosed with DCIS in 2009, over and above the 192,000 who will be diagnosed with invasive breast cancer. Brown says, “A women diagnosed with DCIS has the best prognosis possible today.”
Though there is no explanation for why cancer cells develop, we do know that abnormal genes play a role. Some gene mutations, such as the BRCA1 and BRCA2, are inherited, but most mutations are spontaneous and occur during your lifetime.
Because of the questions about causation and the lack of a cure, Brown says your best defense against breast cancer is an educated offense that includes a regular screening regimen, knowledge of your personal risk and lifestyle choices that reduce that risk.
Source: Breast Cancer, USA Today Supplement, Oct. 2009, p. 5