Searching for a Breast Cancer Vaccine

Researchers are exploring a vaccine that targets and kills breast cancer cells.

November 13, 2008, 3:03 PM

Nov. 13, 2008— -- Ingrid Eikineas, of South Hingham, Mass., was only 35 years old when doctors told her last year that she had breast cancer. The disease had already spread to her bones and liver. It was that aggressive.

"The message was: start talking to your kids about not being around," she said. 

But Ingrid had other ideas.  She began extensive treatment, including radiation and chemotherapy. After a year of treatment, amazingly, she has no signs of cancer. 

To stay cancer-free, she still takes the drug Herceptin. But she knows that eventually, in most women, the drug stops working and the cancer returns.   

"So we know that day is coming," she said. "So in anticipation of that, we try to be a step ahead of the game." 

For Ingrid, that meant testing an experimental breast cancer vaccine, which tries to use her own immune system to target and kill breast cancer cells whenever they might re-appear. 

Click here for information on clinical trials.

"I'm enthused about this vaccine because it targets a protein that is actually involved in causing the cancer," said Dr. Norah Disis, associate professor of medicine in the Division of Oncology at University of Washington and lead investigator of the vaccine's latest clinical trial.  

The vaccine targets a protein specific to "HER-2 positive" breast cancers, which accounts for roughly 25 percent of all breast cancer in the United States. This month, Ingrid received the first of six shots. 

"This vaccine stimulates the type of immune response that creates inflammation, or a danger signal, at the site of the tumor and allows the tumor to appear more foreign to the immune system and create a vigorous immune response" Disis told ABC News.

Breast Cancer Vaccine in Clinical Trials

In preliminary tests, that vigorous immune response often lasted eight years or longer in breast cancer patients.    

"We were surprised because in general it had been thought that patients with cancer, [that] their immune systems couldn't be stimulated this way," Disis said.  

This vaccine is just one of a least 40 now being tested. Many focus on different targets and different types of breast cancers. 

Researchers should know the results within the next five to 10 years.  If the vaccine can keep breast cancer from returning, the next step would be to see if the vaccines, administered much earlier, could protect women from ever developing breast cancer.       

"The likelihood, long-term, of a vaccine therapy being useful is quite high," said Dr. Jack Erban, director of the breast-cancer program at Massachusetts General Hospital. "I am not certain which vaccine, or what type of vaccine, and I think that pioneers like Ingrid make it closer to a day when there will be a vaccine."  

But for women determined to remain cancer free, these experiments hold promise for a future without cancer. 

"If you value life and your loved ones, and your role as a mother, you're going to do whatever you can to stay there," Ingrid said, reading to her daughter. "I'm not ready to leave yet."

To learn more about breast cancer vaccines and a list of where they're being tested, click here:

ABC News Live

ABC News Live

24/7 coverage of breaking news and live events