Moderate exercise may prolong OS in patients with metastatic colorectal cancer
Patients with metastatic colorectal cancer who engaged in moderate exercise for at least 30 minutes a day experienced reduced risks for cancer mortality and progression, according to a phase 3 trial scheduled for presentation at the Gastrointestinal Cancers Symposium.
“We found that an increase in total physical activity was associated with improved PFS and OS,” Brendan John Guercio, MD, resident physician at Brigham and Women’s Hospital, said during a press conference. “We also found that greater walking and nonvigorous activity were associated with improved OS.”
Prior studies have consistently shown a link between regular exercise and improved outcomes in patients with earlier-stage colorectal cancer; however, research has not previously evaluated the effect of regular exercise in patients with distant metastases.
“Sedentary lifestyle is a known risk factor for the development of colon cancer,” Guercio said. “It also has been associated with increased recurrence and mortality in patients with early-stage colorectal cancer. Patients who are active tend to tolerate chemotherapy better and seek more information.”
The analysis included data from 1,231 patients undergoing chemotherapy for metastatic colorectal cancer. Patients self-reported physical activity through a questionnaire and researchers recorded that activity by using a standard measure of metabolic equivalent task (MET)-hours per week. Researchers excluded patients who experienced disease progression or died within 60 days of activity assessment.
OS served as the primary endpoint, and PFS was the secondary endpoint.
Analyses were adjusted for comorbidities, significant weight loss over the previous 6 months, BMI, effects of chemotherapy, patient gender and age.
Researchers compared the least active patients, or those who engaged in less than 30 minutes of physical activity per week, equivalent to less than 3 MET-hours a week, with patients who engaged in 30 or more minutes of moderate activity per day, equivalent to 18 or more MET-hours per week. Results showed that the more active patients had improved OS (HR = 0.81; 95% CI, 0.67-0.98) and PFS (HR = 0.84; 95% CI, 0.71-1).
In a secondary exploratory analysis, patients who spent 4 or more hours per week in nonvigorous physical activity — such as walking, yoga or lawn mowing — demonstrated a 20% OS improvement, and those who spent 5 or more hours per week on these activities demonstrated a 25% OS improvement.
Further, vigorous activities, such as running, were not associated with improved OS or PFS.
“One [reason] might be there were fewer people participating in vigorous activities given this patient population and may not have had sufficient power,” Guercio said. “The safest thing to say is, we don’t know.”
Another question that remains is whether “physical activity [was] making people healthier, or were individuals who are sicker than others just exercising less,” Guercio said.
Nancy Baxter, MD, FRCSC, FACS, PhD, ASCO expert in gastrointestinal cancers, said these results underscore the impact exercise has on the long-term health of patients with advanced cancer.
“Physical activity can be difficult for patients with advanced colorectal cancer, but this study shows that even a small amount of exercise may make a big difference,” she said. “It’s important to help our patients find ways to incorporate moderate exercise into their daily lives, regardless of the stage of their disease.” – by Chuck Gormley
Guercio B, et al. Abstract 659. Scheduled for presentation: Gastrointestinal Cancers Symposium; Jan. 19-21; San Francisco.
Disclosure: Guercio reports no relevant financial disclosures. Please see the abstract for a list of all other researchers’ relevant financial disclosures.