Breast Cancer Health Center

New Approaches to Chemotherapy for Breast Cancer

Combination or Monotherapy?

Experts have long debated whether combination chemotherapy, a number of drugs administered simultaneously, is more or less effective than monotherapy, a single drug given at a time. Recent evidence suggests that it depends on the stage of cancer.

"Clearly," Seidman tells WebMD, "combinations are superior to single agents in adjuvant chemotherapy, which is chemotherapy following radiation or surgery. Experts are constantly tinkering with variations in these combinations to make them more effective and less toxic.

But in cases of metastatic breast cancer, where the cancer has already spread to other parts of the body, Seidman points to numerous studies that indicate that using combination therapy is no better than using single drugs in a sequence. For instance, Seidman says that in the recent results of one study by the Eastern Cooperative Oncology group, using Taxol and doxorubicin Adriamycin together had no advantage over using them sequentially.

Despite the progress that's already been made, Ellis sees this as an area of great potential. "There's a lot more work to be done on dose scheduling and combinations," she says. But according to one theory, she says, "it's fiddling with all these little things that's contributing most to lowering the death rate."

The Future of Chemotherapy

Doctors and researchers are developing still other approaches to breast cancer chemotherapy. While drugs designed to prevent anti-angiogenesis originally attracted a great deal of attention in the press and inside pharmaceutical companies, studies have have been almost uniformly disappointing so far. The recent research into using Avastin, an anti-angiogenesis drug, in advanced breast cancer have not been encouraging, but further studies are planned. Other drugs and treatments are being developed and several institutions are looking into the possibility of a cancer vaccine.

Because of its toxicity and the harm it causes to both healthy and cancerous cells alike, traditional chemotherapy has inherent limitations. "Eventually, I think we'd like to get rid of chemotherapy as we know it," says Seidman. He hopes that as more is learned about breast cancer, experts will continue to develop more targeted approaches to systemic, or full-body, therapy.

One new approach being studied involves using liposomes, molecules that can be artificially filled with a chemotherapy drug and inserted into the body. These liposomes are essentially containers that carry a chemotherapy drug directly to the tumor, sparing the rest of the body unnecessary damage.

Treatment will also become more customized as researchers better understand the genetics of various subtypes of breast cancer. Different types of breast cancer respond better to different treatments. Drugs such as Herceptin -- which is designed to affect a specific type of cancer cell with high levels of the HER2 protein -- are the first new targeted medications. Researchers are also working on developing genetic tests for cancer cells that might allow doctors to identify the kind of cancer and thus determine a person's ideal treatment from the outset.

Seidman reports that at Memorial Sloan-Kettering, breast cancer researchers have been studying the drugs geldanimycin and Gleevec -- the latter is currently used to treat certain types of abdominal cancer and leukemia -- for their targeted effects on cancer cells. Results are a ways off, but as more precise and focused ways of attacking cancer become possible, doctors may someday be able to stop relying on the generic, toxic chemotherapy agents that have been used for decades.