Healthy Diet and Exercise Improve Response to Chemotherapy in Women With Breast Cancer
A healthy diet and exercise was linked to higher pathologic complete response (pCR) rates in women who received neoadjuvant chemotherapy for early-stage, hormone receptor-positive, HER2-negative breast cancer and triple-negative breast cancer, according to a study.
The research was published online on Sept. 1, 2023, by the Journal of Clinical Oncology. Read the abstract of “Randomized Trial of Exercise and Nutrition on Chemotherapy Completion and Pathologic Complete Response in Women With Breast Cancer: The Lifestyle, Exercise, and Nutrition Early After Diagnosis Study.”
Doctors call treatments given before surgery neoadjuvant treatments.
What is pCR?
One way doctors judge the effectiveness of neoadjuvant treatments is to look at the tissue removed during surgery to see if any actively growing cancer cells are present. If no active cancer cells are present, doctors call it a “pathologic complete response” or pCR.
A number of studies have shown a link between pCR after neoadjuvant chemotherapy for breast cancer and better disease-free survival, as well as better overall survival.
Disease-free survival is how long a person lives without the breast cancer coming back. Overall survival is how long a person lives, with or without the breast cancer coming back.
About the study
Called the Lifestyle, Exercise, and Nutrition Early After Breast Cancer (LEANer) trial, the study had two aims.
The first was to see if exercise and a healthy diet would improve chemotherapy completion in women diagnosed with early-stage breast cancer. The researchers assessed completion rates with a measurement called relative dose intensity (RDI). RDI is the ratio of the amount of chemotherapy a doctor prescribes to the amount of chemotherapy someone actually receives. So if a woman has a dose reduction or has to skip a dose of chemotherapy, the RDI would be less than 100%.
The second aim was to see if exercise and a healthy diet would improve pCR rates in women receiving neoadjuvant chemotherapy.
The study included 173 women with an average age of about 53 and an average BMI of 29.7 who were receiving treatment at either Yale-New Haven Hospital or the Dana-Farber Cancer Institute:
71% were white
14% were Black
8% were Hispanic
51% were diagnosed with stage I breast cancer
37% were diagnosed with stage II breast cancer
11% were diagnosed with stage III breast cancer
57% were diagnosed with hormone receptor-positive, HER2-negative breast cancer
17% were diagnosed with HER2-positive breast cancer
25% were diagnosed with triple-negative breast cancer
42% received neoadjuvant chemotherapy; all the women who received neoadjuvant chemotherapy were diagnosed with either hormone receptor-positive, HER2-negative breast cancer or triple-negative breast cancer
25% received Taxotere (chemical name: docetaxel) and Cytoxan (chemical name: cyclophosphamide)
25% received dose-dense Adriamycin (chemical name: doxorubicin) and Cytoxan, followed by dose-dense Taxol (chemical name: paclitaxel)
25% received dose-dense Adriamycin and Cytoxan, followed by Taxol
When they first joined the study, the women completed baseline questionnaires asking about their medical history, as well as how much they exercised and what they ate.
Then the researchers randomly split the women into two groups: a diet and exercise group and a usual care group.
There were 87 women in the diet and exercise group. They participated in diet counseling and exercise sessions with registered dietitians who were certified specialists in oncology nutrition, and also had additional training in exercise science.
There were two goals:
To have the women do 150 minutes or more of moderate- to vigorous intensity exercise per week or 75 minutes per week of vigorous exercise, plus two sessions of resistance training per week. The exercise plan included a progressive strength training program and emphasized brisk walking.
To have the women eat a mainly plant-based diet, including eating five or more servings of fruits and vegetables per day, 25 or more grams of fiber per day, less than 30 grams of added sugar per day, and 18 or fewer ounces of red meat per week. The women were also asked to limit how much processed food they ate and drink one or fewer alcoholic beverages a day.
There were 86 women in the usual care group. They were able to talk to a registered dietician and attend survivorship clinics any time during their treatment. At the end of the study, the researchers offered the women a one-on-one counseling session with one of the registered dietitians who led the diet and exercise group and gave them the diet and exercise group study materials.
The women’s chemotherapy regimens lasted about 3.3 months.
At the end of chemotherapy, the results showed that women in the diet and exercise group:
increased the number of minutes they did moderate- to vigorous-intensity exercise per week from 27 to 143; at the beginning of the study only 10% of the women in this group did resistance training, and after completing chemotherapy, 71% did resistance training
increased the daily servings of fruits and vegetables they ate from four to five and increased the amount of fiber they ate a day from 18 grams to 19 grams
About 33% of the women had a chemotherapy dose reduction.
The RDI was:
92.9% for women in the diet and exercise group
93.6% for women in the usual care group
Among the women who received neoadjuvant chemotherapy, women in the diet and exercise group were more likely to have a pCR:
53% of women in the diet and exercise group had a pCR
28% of women in the usual care group had a pCR
“Although a diet and exercise intervention did not affect RDI, the intervention was associated with a higher pCR in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative and triple-negative breast cancer undergoing neoadjuvant chemotherapy,” the researchers concluded.
What this means for you
Eating a healthy diet and exercising are extremely important to being as healthy as you can be during and after breast cancer treatment. They’re so important that many experts recommend treating exercise and eating healthy as part of your breast cancer treatment plan.
This study strongly suggests that exercise and healthy eating can improve pCR rates after neoadjuvant chemotherapy for women diagnosed with either triple-negative or hormone receptor-positive, HER2-negative breast cancer. The findings reinforce results from another 2023 study showing that women diagnosed with high-risk breast cancer who most closely follow cancer prevention lifestyle recommendations had a lower risk of recurrence and death from the disease.
If you’re receiving chemotherapy, we know it can be hard to think about healthy eating and exercising, especially if you’ve never done either before.
You may want to start slowly by taking a walk every day and gradually increasing the amount of time you walk. Resistance exercise doesn’t have to mean weight lifting. You can start by sitting in a chair and lifting two soup cans.
Listen to The Breastcancer.org Podcast episode featuring Sami Mansfield, a certified exercise trainer, talking about how “exercise snacks” can help people start exercising.
Exercise for People Diagnosed With Metastatic Breast Cancer
Feb 23, 2019It’s the same with your diet. You don’t have to change everything at once. Try to make one small change at a time. You can add one serving of vegetables to your diet for a month and then try adding one more.
Listen to The Breastcancer.org Podcast episode featuring Amy Bragagnini, RD, MS, discussing the benefits of healthy eating during treatment, as well as how to start eating healthier.
Updated on October 18, 2023