Elizabeth Edwards Taught Lesson About Decisions to End Treatment

Dec. 7, 2010— -- Just a day after announcing she stopped all cancer treatment, Elizabeth Edwards has died, ABC News has confirmed.

Between September and late November, Edwards' health went into decline. Her breast cancer spread to her liver, and eventually reached the point where medical treatment was ineffective.

Although she was well enough to make public appearances just a few months ago, medical experts who are not involved with Edwards' treatment say it's not unusual for metastatic breast cancer to progress quickly into its final stages.

"Once the last of all of the likely therapies stops working, it is typical for deterioration to be quite rapid," said Dr. Harry D. Bear, professor of oncology at Virginia Commonwealth University in Richmond, Va.

Edwards' cancer was reportedly the estrogen receptor-positive (ER-positive) type, meaning the cancer grows in high-estrogen environments. Doctors say it's the most common form of breast cancer, and is also the type that leads to the most deaths.

"More breast cancer patients die from ER-positive cancer that's become resistant to anti- hormone drugs than any other type of cancer," said Dr. Matthew Ellis, professor of medicine at Washington University School of Medicine in St. Louis, Mo. "The cancer relapses despite the use of these drugs."

Medical experts say how long to continue therapy for metastatic breast cancer, which will eventually become resistant to therapy, is a difficult decision. It requires balancing the effectiveness of treatment and a patient's quality of life.

"The decision when to stop chemotherapy and focus on symptom management is one of the mostgut-wrenching we face, especially in breast cancer, because there are so many therapies with some chance of working, but that chance decreases with each successive regimen, while [treatment] toxicity remains the same or increases," said Dr. Daniel Hayes, clinical director of the Breast Oncology Program at the University of Michigan Comprehensive Cancer Center in Ann Arbor.

Experts also say the decision must involve regular communication between doctor and patient through the course of the disease.

"It begins at the time of diagnosis and is very patient-specific," said Dr. R. Sean Morrison, professor of palliative medicine at the Mount Sinai School of Medicine in New York. "We want to understand what are their values and goals and what are values of treatment."