Researchers Test Vaccine Against Breast Cancer

Research in the fight against breast cancer has led to what could be a promising new development; a vaccine that kills tumors.

Researchers at the University of Pennsylvania report that a short course of vaccination with a vaccine made partly from the patient’s own cells triggers a complete tumor eradication in nearly 20 percent of women with ductal carcinoma in situ (DCIS), an early breast cancer.

While 20 percent sounds like a small number, the scientists say more than 85 percent of patients treated appear to have a sustained immune response after vaccination, which may reduce their risk of developing a more invasive cancer in the future.

Most effective in early treatment

The researchers say the results provide new evidence that therapeutic breast cancer vaccines may be most effective for early, localized disease, and when the treatment attacks a protein critical to cancer cell survival.

“I think these data more than prove that vaccination works in situations where the target is right,” said the study’s leader, Dr. Brian Czerniecki. “Previous vaccines targeted tissue antigens that were expressed on the cancer cells, but were not necessary for tumor survival. So a vaccine response would cause the tumor to just stop expressing the antigen and the tumor would be fine.”

The new vaccine, he says, attacks critical cells.

“If we knock it out with the immune response, we cripple the tumor cells,” he said.

What's next

While the numbers of patients treated in the trial are relatively small, Czerniecki thinks they will have some idea whether the vaccination reduces the risk of disease recurrence within the next two years. In the meantime, the team continues enrolling patients in a larger study, is designing another study to test the approach in women with early invasive breast cancer, and also plans to test vaccination with additional antigens.

There are two main types of breast cancer – ductal carcinoma, which starts in the milk ducts, and lobular carcinoma, which start in the lobules area of the breast. Ductal carcinoma is the most common type of breast cancer.