Stage III colon cancer patients adhering to ACS Nutrition and Physical Activity Guidelines for Cancer Survivors after diagnosis had a 42% lower risk of death.
Investigators of the prospective CALGB 89803/Alliance trial have uncovered a significant disease-free survival (DFS) and overall survival (OS) benefit for stage III colon cancer patients who adhered to American Cancer Society (ACS) Nutrition and Physical Activity Guidelines for Cancer Survivors after receiving their diagnosis.
In this cohort study of 992 patients with colon cancer, published online first in JAMA Oncology, Erin Van Blarigan, ScD, of the University of California, San Francisco, and colleagues found that “a lifestyle consistent with the ACS guidelines was associated with a 42% lower risk of death during the study period,” and noted that the 5-year survival rate may be higher in colon cancer patients who follow these guidelines during and after treatment.
The ACS guidelines include maintaining a healthy body weight; engaging in regular physical activity; and consistently following a diet including vegetables, fruits, and whole grains. Van Blarigan and colleagues noted that the ACS first published guidelines for nutrition during and after cancer treatment in 2001.
More than 1.3 million people in the United States are survivors of colorectal cancer (CRC). While studies have shown that healthy people who follow the ACS guidelines have a lower risk of overall and cancer-related mortality-and that adherence improves quality of life in CRC survivors, the effect of ACS guideline adherence on survival rates and recurrence risk in patients with colon cancer was previously unknown, Van Blarigan et al wrote.
The study included 992 patients with stage III colon cancer who were enrolled in the Cancer and Leukemia Group B (CALGB) 89803 randomized adjuvant chemotherapy trial from 1999 through 2001. (CALGB is now part of the Alliance for Clinical Trials in Oncology.) Nearly half (n = 430) of the patients were women, and the mean age was about 60 years (range, 21–85 years). The data were analyzed between November 2016 and December 2017.
Van Blarigan and coinvestigators assigned each patient an ACS guidelines score between 0 and 6, based on body mass index; physical activity; and intake of vegetables, fruits, whole grains, and red/processed meats. Patients with higher scores had healthier behaviors. They also assigned “lifestyle” scores from 0 to 8 based on alcohol intake and other factors. Lifestyle was assessed both during chemotherapy and 6 months following completion of treatment.
Over a 7-year median follow-up of the 992 eligible patients, there were 335 recurrences and 299 deaths (43 of which occurred without disease recurrence). Compared with patients who had an ACS guidelines score of 0 to 1 (26% of all patients), patients with a score of 5 to 6 (a lifestyle consistent with the ACS guidelines; 9% of all patients) had a 42% lower risk of death during the study period (HR, 0.58; 95% CI, 0.34–0.99; P = .01 for trend) as well as improved DFS (HR, 0.69; 95% CI, 0.45–1.06; P = .03 for trend).
With alcohol consumption included in the score, the adjusted HRs comparing patients with scores of 6 to 8 (n = 162) against patients with scores of 0 to 2 (n = 187) were 0.49 for OS (95% CI, 0.32–0.76; P = .002), 0.58 for DFS (95% CI, 0.40, 0.84; P = .01), and 0.64 for recurrence-free survival (95% CI, 0.44–0.94; P = .05).
There was a 9% absolute reduction in risk of death at 5 years for stage III colon cancer patients with a score of 5 or 6, compared with patients whose scores ranged from 0 to 4.
In conclusion, Van Blarigan and coauthors wrote that “it is plausible that following the ACS guidelines after colon cancer diagnosis inhibits recurrence and death. Extensive data suggest that a healthy body size, physical activity, and diet rich in vegetables, fruits, and whole grains improves insulin sensitivity, decreases inflammation, and increases vitamin D levels. These biomarkers have all been consistently associated with colorectal cancer survival.”