Breast Cancer

At a glance

  • The most common cancer in women is breast cancer, aside from skin cancer.
  • Risk factors include age, personal and family history of cancer, reproductive and menstrual history, ethnicity, breast density, lack of physical activity, and consumption of alcohol
  • Signs and symptoms of breast cancer, described below, are fairly easy to discover with a minimum of training and vigilance.
  • Early detection of breast cancer improves the chances of successful treatment.
  • New techniques are constantly being developed to improve the detection, diagnosis, and treatment of breast cancer. To stay up to date with the latest developments, our Breast Cancer Specialist teams attend conferences and speak interdisciplinary.

Sabrina is a breast cancer survivor from the San Francisco Bay Area that received treatment at Diablo Valley Oncology.

The Statistics of Breast Cancer

Aside from non-melanoma skin cancer, breast cancer is the most common form of cancer in women. The number one cause of cancer death in Hispanic women, and the second most common cause of cancer death in nearly all other women is breast cancer. In 2016, an approximate 246,660 women will be diagnosed with breast cancer and 40,450 will die from the disease. Breast cancer affects the lives of millions of women as well as their families, friends and communities. But there is good news, when discovered, its treatable and in many cases, survivable if not completely curable.

What is Breast Cancer?

Breast cancer is formed in the tissues of breast, most commonly in the ducts and lobules. It is estimated that 1 in 8 American women will get breast cancer at some time in their lives. Men can also develop breast cancer, but it is far less common than in women.  


Breast Anatomy The breasts are composed of fatty tissue that contains the glands responsible for milk production in late pregnancy and after childbirth. Within each breast, there are about 15 to 25 lobes formed by groups of lobules, the milk glands. Milk glands produce milk and the ducts carry it to the nipples. The breast tissue extends up to the collarbone on top and the armpits on the side. Breasts also contains lymphatic vessels which connect with a network of lymph nodes. These are located around the breasts’ edges or in nearby tissues of the armpits and collarbone. Lymph nodes play a central role in the spread of breast cancer.

How Breast Cancer Occurs

In the normal human body, the increase in number and size of your cells is tightly regulated. Every day, a certain number of cells die, and are replaced by an appropriate number of new cells. Sometimes, an abnormal group of cells in the breast tissue begins to grow uncontrollably. They also don’t respond to the body’s signals that should trigger cell suicide, causing them to live longer than normal cells do. The build up of these extra cells form a mass of tissue which is called a lump or tumor. These tumors can be benign or malignant. Benign tumors are considered non-cancerous and are at little risk of spreading to other parts. Malignant tumors are considered cancerous, have the potential to metastasize, and can grow very rapidly and aggressively.

Risk Factors

Although the precise causes of breast cancer are not fully understood, a number of risk factors have been defined.  Some of these risk factors include:
  •  Age
  • Personal and family history of cancer
  • Reproductive and menstrual history
  • Ethnicity
  • Breast density
  • Lack of physical activity
  • Consumption of alcohol
Some risk factors can be managed or avoided, while others, such as genetics or exposure to radiation or toxins, cannot be aptly managed or avoided. Read more: Symptoms & Diagnosis of Breast Cancer Read more: Breast Cancer Stages & Treatment Schedule an appointment with our Bay Area breast cancer specialist, Dr. Tiffany Svahn, or one of our other San Francisco Bay Area breast cancer specialists.