Duke Medicine: Customized breast cancer treatment, one woman at a time

When Nixon declared war on cancer in the 1970s, we attacked it with our biggest weapons. “The medical mindset was to bomb the holy heck out of stuff, dosing chemo until people couldn’t stand it anymore,” says Duke breast oncologist Kimberly Blackwell, MD.

A lot has changed since then. As research reveals more about the causes and vulnerabilities of various types of tumors, the war on cancer is experiencing its own revolution.

The outcome of each woman’s fight against breast cancer hinges on many factors, says P. Kelly Marcom, MD, clinical director of Breast Medical Oncology and director of the Hereditary Cancer Clinic at Duke. “There is the individual’s inherited genetic traits, her environmental exposures, the biology of her particular cancer, and more. Basically we are up against a different cancer in every person we treat.”

Scientists at Duke and elsewhere are using new prevention and treatment strategies pinpointed to the characteristics of each woman and her disease. This new brand of care is known as personalized medicine. As Dr. Marcom puts it, “Find out exactly what someone needs, give them that and nothing more.”

Many investigators believe that genomic analysis is the fast track to personalized treatment that is more effective and less toxic. In the same way that it’s now possible to generate a profile of a person that spells out all the gene expressions she carries in her DNA, it’s also possible to generate a genomic profile of a tumor.

Another frontier in cancer care is targeted therapies. Sometimes referred to as the “chemo of the future,” targeted therapies are different from chemotherapies in that they act on a specific function in the tumor cell, whereas chemotherapies generally wipe out any cells in the body that are rapidly dividing. For example, the targeted therapy lapatinib blocks the action of the HER2 gene, which mutates to become overactive in about a quarter of women with breast cancer, causing more aggressive cancer.

“We’ve been reluctant to let go of chemo because it takes a long time to develop and incorporate new treatments,” Dr. Blackwell says. “But we’re showing that when we understand the mechanisms behind a woman’s tumor, we can give her the right drugs; we don’t always have to have the toxicity. It’s starting to get cancer more in line with other chronic conditions like lung, kidney, and heart disease, where we manage medications and lifestyle.”