Would you undergo chemotherapy if it weren’t absolutely necessary? Of course not. Would you be willing to deal with the unpleasant side effects if it would save your life? Almost certainly.
It’s the middle ground where things get muddy.
When it’s unclear if chemotherapy is necessary in a cancer patient, doctors have generally adopted a “better-safe-than-sorry” approach, which makes perfect sense when dealing with someone’s life. But a new, large-scale study shows that thousands more women with breast cancer could forgo chemotherapy without any increased risk. In fact, the new findings could spare 60,000 American breast cancer patients the ordeal of chemotherapy every year.
Doctors were aware that some women with one of the most common forms of early-stage breast cancer did not always need chemotherapy, but where to draw the line between those who would benefit and those who wouldn’t was unclear. The new TAILORx study (Trial Assigning Individualized Options for Treatment) set out to draw that line.
The study started in 2006 and began with 10,253 women between the ages of 18 and 75. Of those, 9,719 completed follow-up information and were included in the results.
Researchers looked at the effectiveness of chemotherapy in women with early-stage cancer that had not spread to lymph nodes, was hormone-positive, HER2-negative, and could not be targeted by the drug Herceptin. This type accounts for about half of all breast cancer cases in the United States. Generally these women would have been treated with surgery and hormone-blocking drugs, but many would also have been given chemotherapy as a way to ensure the death of any stray cancer cells.
Study participants were given a test called Oncotype DX, which takes a biopsy tumor sample (after the tumor is removed) and measures the gene activity in the cancer cells and the cancer’s response to hormone therapy. Based on the cancer’s responses, the Oncotype DX gave each woman a recurrence score from 0 to 100. The higher a woman’s score, the higher the likelihood of recurrence. The Oncotype DX test is the most common used gene analysis test in the United States, and is usually covered by insurance.
Previous research had determined that women receiving scores of 10 or below would not benefit from chemotherapy, and those with scores of 25 would. But a majority of women eligible for the test receive intermediate scores, between 11 and 24. What was best for these women was unclear. To find the best course of treatment, study participants with scores between 11 and 24 were split into two groups. All underwent surgery and radiation therapy, but half also underwent endocrine therapy alone while the other half underwent endocrine therapy and chemotherapy.
After nine years, the two groups were not statistically different. In the endocrine-only group, 93.9 percent were still living; in the endocrine and chemo group, 93.4 percent were still living, and 83.3 percent of women in the endocrine group did not have signs of invasive disease; the same was true for 84.3 percent of the endocrine and chemo group. Researchers concluded that for women with recurrence scores between 11 and 24, chemotherapy did not make a significant difference in outcomes.
“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,” said Dr. Sparano, the leader of the study.
Researchers did note that chemotherapy was beneficial to women with recurrence scores between 16 and 25 who were 50 or younger at time of diagnosis (median age of diagnosis is 62).
So what does this mean? Tens of thousands could be spared chemo every year, and doctors now have a clear idea when chemo is appropriate and when it’s overkill.
Dr. Larry Norton, of Memorial Sloan Kettering Cancer Center, is excited about the implications of the study. “I think this is a very significant advance,” he said. “I’ll be able to look people in the eye and say, ‘We analyzed your tumor, you have a really good prognosis and you actually don’t need chemotherapy.’ That’s a nice thing to be able to say to somebody.”
The study and its results were presented on Sunday, June 3, 2018 at a meeting of the American Society of Clinical Oncology.
Chemotherapy is a powerful part of cancer treatment. It has and will continue to save lives. But the side effects of chemotherapy extend beyond hair loss and nausea: it can cause nerve damage, increase risk of infection, and damage to the reproductive system.
If patients could forgo chemotherapy without fear of repercussion, it would save inestimable amounts of pain, worry, and financial burden. The Oncotype DX test could identify up to 85 percent of women with early stage breast cancer who can safely pass on chemotherapy. The scale and quality of this study mean that doctors are paying attention to the results, and fewer breast cancer patients may be advised to undergo chemotherapy in the near future.
remember the participants
The results are encouraging, but it would not have been possible without the thousands of women who agreed to be part of the clinical trial. These were women who understood that they were taking a journey into unsure territory for the benefit of future cancer patients. When Bari Brooks, for example, found out she had cancer when she was 49, she didn’t hesitate to get involved in the study—even though it meant she may or may not get chemo.
“It wasn’t even a decision I had to think about,” she said. “It was yes, I want to do it… This was a situation where I could also contribute. I was honored and grateful to be part of it.”
In a study like the TAILORx study, women took a chance on behalf of women, and men, that they’d never even meet. We’re grateful to them, and for all the researchers working to make cancer treatment without chemotherapy an option for thousands more patients across the country.
Keep fighting, friends.
Katie Taylor started writing in 5th grade and hasn't stopped since. Her favorite place to pen a phrase is in front of her fireplace with a cup of tea, but she's been known to write in parking lots on the backs of old receipts if necessary. She and her husband live cozily in the Pacific Northwest enjoying rainy days and Netflix.