The breast cancer vaccine is a vaccination that is under development to prohibit the formation of breast cancer. Though the vaccine has shown promising results in clinical trials performed on animals, it may be some time before it is approved for humans. Vaccines for cervical cancer and liver cancer have been developed and approved for human use, but unlike breast cancer, both of these cancers are believed to be the result of viruses that can be treated without involving healthy tissue. Breast cancer is considered the result of abnormal cell growth unrelated to any type of virus, which raises the risk that a breast cancer vaccine may actually damage healthy tissue as it attempts to destroy or prohibit cancerous growths. Clinical trials with humans are under way, but the outcome of the treatment is still unclear.
Vaccines created to combat viruses are believed to be much safer than the type of vaccine being developed to fight breast cancer. Viruses are foreign bodies that invade and attack healthy tissue inside the body, but with breast cancer, no such completely foreign body has yet been identified. Until it is improved upon, the breast cancer vaccine instructs the immune system to attack naturally occurring cell growth, which could have adverse effects. Research to develop a safe breast cancer vaccine is targeted toward finding some type of cell growth within cancerous tumors that may not be naturally occurring within the body.
Scientists have isolated an enzyme called a-lactalbumin that they believe may be responsible for cancerous cell growth within breast tissue. Though this enzyme is not considered a foreign body, it is normally only produced when women are lactating, manufacturing milk with the mammary glands. This enzyme, however, is also present within cancerous tumors inside the breast. The breast cancer vaccine targets this enzyme as it would a viral invader. In clinical trials with animals, this method has generally achieved outstanding results.
It is believed that one-eighth of all women may be at risk for breast cancer at some time in their lives. Breast cancer is considered a genetic type of cancer, meaning women are born with a gene that is predisposed to mutate into the disease. Development of a breast cancer vaccine could potentially save thousands of lives each year. Most researchers agree that for initial use, the breast cancer vaccine would probably be administered to women believed to be at high risk for the disease. This includes women over the age of 40 with a history of breast cancer in their families.