Colon cancer patients with healthy lifestyle have longer disease-free survival, study finds

May 18 2017

A study of 992 patients with stage III colon cancer found that those who reported a healthy lifestyle during and following adjuvant (post-surgery) treatment had a 42% lower chance of death and a trend for lower chance of cancer recurrence than those who had less healthy lifestyles. The study will be presented at the upcoming 2017 ASCO Annual Meeting in Chicago.

"There are over 1.3 million colorectal cancer survivors in the United States. These patients need survivorship care, including guidance on what they can do to lower their risk of recurrence," said lead study author Erin Van Blarigan, ScD, Assistant Professor of Epidemiology and Biostatistics, University of California San Francisco. "In response to patient interest and need, the American Cancer Society (ACS) published 'Nutrition and Physical Activity Guidelines for Cancer Survivors' in 2012, but it is not known if following the guidelines after cancer diagnosis is associated with improved outcomes."

This study found that colon cancer patients whose lifestyle matched the ACS guidelines had longer disease-free survival and overall survival.

About the Study
The patients were part of a clinical trial that enrolled from 1999 to 2001 and looked at the effect of two types of adjuvant chemotherapy for colon cancer on cancer recurrence and death. Lifestyle was assessed twice as part of the trial using validated surveys. Patients were assigned a score from 0-6 that measured the degree to which their lifestyle matched the ACS guidelines for cancer survivors. A score of zero indicated no healthy behaviors while a score of six indicated that the patients observed all of the healthy behaviors. Specifically, researchers assessed individuals based on recommendations for:

• Maintaining a healthy body weight
• Engaging in regular physical activity
• Eating a diet rich in whole grains, vegetables, and fruits and low in red meat and processed meat

Alcohol use was also included in the assessment as it is included ACS Guidelines for Cancer Prevention.

Each of the healthy behaviors was equally weighted, but assessing dietary components was a bit more complex as the researchers had to score red and processed meat, whole grains, and vegetables and fruits individually and then build an overall dietary score.

Key Findings
Over a median follow-up of 7 years, the 91 survivors who had the highest healthy lifestyle scores (5-6 points) had a 42% lower risk of death and a trend for reduced chance of recurrence than the 262 survivors with the lowest lifestyle scores (0-1 points). When drinking alcohol was included in the score, the 162 survivors with the highest lifestyle score (6-8 points) had a 51% lower chance of death and a 36% lower chance of cancer recurrence than the 187 survivors who had the lowest healthy lifestyle scores (0-2 points). The associations were not driven by any particular lifestyle factor; body weight, regular physical activity, and a healthy diet were all important.

The researchers note that many cancer survivors have ongoing health problems, such as diabetes or heart disease, and a healthy lifestyle can help improve overall health. They further emphasize that their study's novel findings indicate that a healthy lifestyle may improve colon cancer-specific outcomes as well.

"It should be emphasized that the authors are not suggesting that a healthy life-style alone should be considered a substitute for standard chemotherapy and other treatments for colon cancer, which have dramatically improved survival. Rather, patients with colon cancer should be optimistic, and they should eat a healthy diet and exercise regularly, which may not only keep them healthier, but may also further decrease the chances of the cancer coming back," said Dr. Hayes.

Next Steps
"Our research team is conducting clinical trials to evaluate the feasibility and acceptability of digital health lifestyle interventions, such as Fitbit for colorectal cancer patients," said Dr. Van Blarigan. "If our interventions are acceptable and useful to patients, we will test their impact on risk of cancer recurrence and mortality in future studies."