70% of Women with Common Breast Cancer Are Better Off Skipping Chemo, New Study Finds

June 11, 2018 at 11:54 am

New genetic test can spare most breast cancer patients chemotherapy, which study finds is useless for most women

Chemotherapy can have devastating side effects, including bone loss, osteoporosis, heart and vision problems, anemia, a weakened immune system, hair loss, diarrhea, fatigue and memory loss.

Luckily, 70% of women with the most common type of breast cancer don’t need it, according to a new study published by the New England Journal of Medicine last week.

The most common type of breast cancer in the world is hormone-receptor positive, HER2-negative, node-negative cancer.

The primary treatment for this type of cancer is estrogen-blocking drugs along with chemotherapy to lower the risk of recurrence.

A new genetic test can determine the likelihood of the cancer recurring in a particular woman.

Using the test in the new study, researchers found at least 70 percent of women with this common breast cancer have such a low chance of recurrence that they can safely skip chemotherapy.

In fact, after following women with this type of cancer for 10 years, researchers found 83.3 percent of women who skipped chemo did not develop recurring cancer, while only 84.3 percent of women who took the chemo had the same luck.

In other words, the chemo improved their chances of recurrence by 1 percent.

Furthermore, the women who skipped the chemo had a slightly better overall survival rate of 93.9 percent, compared to 93.8 percent of those who received chemo.

“I’m delighted,” Dr. Otis Brawley, chief medical and scientific officer for the American Cancer Society, told CNN. “I’ve been worried for a long time about unnecessary treatment for cancer, and unnecessary side effects from chemotherapy.”

“Now with these genomic tests, we are finding that we have multiple types of breast cancer, perhaps several dozen, and we are being able to tailor our therapies to the type of breast cancer every woman has.”

Thirty percent of the women in the trial did have evidence of cancer hiding elsewhere in their bodies. For these women, the researchers still recommend chemotherapy.
“We’ll give women in this group about six months of chemotherapy,” Brawley said.
“These findings, showing no benefit from receiving chemotherapy for most patients … will go a long way to support oncologists and patients in decisions about the best course of treatment,” Dr. Jeffrey Abrams, associate director of the National Cancer Institute’s Cancer Therapy Evaluation Program, said in a statement.