Hope on the Horizon for Advanced Breast Cancer
New Treatments Are Prolonging Survival and Improving Quality of Life
Isaacs predicts that state-of-the-art care
for advanced breast cancer in the future may also combine chemotherapy with
newer types of drugs: immunotherapy, hormone therapy, and even
"The big move is to look at novel
agents given in conjunction with standard chemotherapy. That may be a way to
really make a dent on prolonging survival," Isaacs says. Genentech, the
company that developed Herceptin, is now testing an antibody that blocks a
growth factor that's important to the formation of new blood vessels. Such an
antibody could work in combination with chemotherapy to choke off the growth of
In a one-two punch, Herceptin is also being
combined with the chemotherapy drugs, Taxol and carboplatin (brand name
Paraplatin), in a large clinical trial by the U.S. Oncology Group and McGill
University. Other studies have shown potential in Gemzar -- a drug currently
approved to treat other types of cancer -- especially for women with metastatic
The Promise of Vaccines
At the University of North Carolina's
Lineberger Cancer Center, scientists are about to complete a early human study
of a therapeutic vaccine to treat advanced breast cancer. This type of cancer
vaccine doesn't work the way that vaccines for infections like measles do.
Those are given to people to prevent disease. Therapeutic cancer vaccines are
being studied to help the body's immune system "rev up" to fight the
disease. Initially, at least, they would be used in women who have exhausted
all other treatments.
In this case, the vaccine is customized for
each individual woman. Doctors take a woman's dendritic cells -- a type of
white blood cell that alerts the immune system to the presence of abnormal
proteins present in breast cancer cells -- and engineer them to boost their
response against a particular type of abnormal protein.
"We're looking for ¼ regression of
established tumors. By definition, this means at least a 25% shrinkage of
established tumors," said researcher Jonathan Serody, MD, when the trials
began. He can't say yet whether they got the expected response, but he notes
that the vaccine was well tolerated by the dozen or so women in the trial.
Serody expects the vaccine to be most effective in combination with other
treatments, such as hormone therapy or chemotherapy. The study at the
University of North Carolina is only one of several that are evaluating
possible vaccines for breast cancer.
"With things like vaccines, combination
therapies, and other fascinating possibilities, we're starting to look beyond
standard chemotherapy and into novel agents to attack advanced breast
cancer," says Isaacs. "We're developing an array of treatments that
work by different mechanisms of action, that give women with advanced breast
cancer more options than they've ever had before."