Many Breast Cancer Patients May Not Require Chemotherapy

Health U.S.

According to a major new study, many women diagnosed with early-stage breast cancer may forego chemotherapy with minimal risk to their health or their overall cancer treatment. They study is to be presented today at a meeting the American Society of Clinical Oncology in Chicago.

The study, called TAILORx, began in 2006 and was funded by the U.S. & Canadian governments, corporations and philanthropic groups.

Over 266,000 women will be diagnosed with breast cancer this year in the U.S. and about 41,000 of them will die. Chemotherapy, the most common treatment carries with it harsh side effects. Aside from the fatigue, hair loss and nausea, it can also cause heart and nerve damage and increase the risk of leukemia for patients later in life.

Oncotype DX, is the most widely used test in the U.S. used to evaluate genes involved in cancer recurrence. The test is usually conducted for patients with early stages of the disease – advanced tumors usually require chemotherapy because they have spread to lymph nodes and other places.

Oncotype DX assigns scores from 0 to 100. Patients who score 10 and below on the test can usually bypass chemotherapy, while chemotherapy is strong recommended for patients who score above 25. Most patients score between 11 and 25. The large question in breast cancer treatment has been what to do with patients in that range.

Oncotype DX was good for separating patients who did not need chemotherapy as well as patients who required it from the patient pool. But doctors couldn’t agree on what to do with patients in the middle. Which is how TAILORx came about.

TAILORx included 10,253 women ages 18 to 75. Of 9,719 patients with complete follow-up information, 69% had intermediate scores of 11 to 25 on Onctoype DX. Some of these patients were assigned chemotherapy at random, some were not.

After nine years the groups were analyzed for cancer recurrence and survival rates. The cancer-free rate for the chemotherapy group was 84.3%. The rate for the group that did not receive chemotherapy was 83.3%. The overall survival rate for the chemotherapy group was 93.8%. For the non-chemo group it was 93.9%. The benefit of chemo for patients in the intermediary group of Oncotype DX scores was statistically insignificant in other words.

“We can spare thousands and thousands of women from getting toxic treatment that really wouldn’t benefit them,” Dr. Ingrid A. Mayer, from Vanderbilt University Medical Center, one of the authors of the study, told The New York Times. “This is very powerful. It really changes the standard of care.”

Study lead Dr. Joseph A. Sparano of Montefiore Medical Center in New York echoed the sentiments. “The results indicate that now we can spare chemotherapy in about 70 percent of patients who would be potential candidates for it based on clinical features,” he said.

Drs. Sparano and Mayer sounded a note of caution however: The data from the study showed that some women 50 and younger may benefit from chemotherapy even if they score in the intermediate range of 11-25. The reasons are unclear, but they said those women required extra-careful consultation. Most diagnoses of breast cancer in the U.S. occur in older women – the median age for diagnosis is 62.

Photo by Staff Sgt. Alexander Martinez, U.S. Air Force

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