The impact of physical activity on patients with stage III colon cancer: Findings from Intergroup trial CALGB 89803.

3534 Background: Regular physical activity (PA) is strongly associated with a reduced risk of developing colon cancer. The influence of PA on the outcome of patients with established colon cancer is unknown. METHODS: We prospectively studied recreational PA among 816 patients with stage III colon cancer enrolled in a randomized trial of post-operative adjuvant chemotherapy (bolus 5-fluorouracil/leucovorin +/- irinotecan). Patients completed detailed surveys of various non-occupational activities midway through adjuvant therapy (Q1) and then again 6 months after completion of therapy (12-14 months after enrollment, Q2). Levels of PA were measured as total metabolic equivalent tasks (MET)-hours-per-week scores & divided into quintiles. We computed Cox proportional hazards for disease-free survival (DFS) and overall survival (OS) according to quintiles of PA as measured on Q2. DFS and OS were measured from completion of Q2 to recurrence or death (DFS) and death (OS), excluding events within the 1(st) 90 days to avoid biases of decreased activity due to underlying disease. Median follow-up after the post-chemotherapy questionnaire was 2.4 years. RESULTS: Levels of PA were associated with significantly improved DFS among patients with stage III colon cancer. After adjustment for age, gender, baseline performance status, N stage, T stage, preoperative CEA, bowel obstruction and perforation, level of differentiation, treatment arm, and body mass index, the hazard ratio (HR) for DFS for individuals in the highest quintile (>25 MET-hours/week, eg. jog 3-4 hours/week or brisk walk [3-4 mph] daily) was 0.65 (95% CI, 0.38-1.11; p for trend = 0.02) compared to those in the lowest quintile of PA. This relationship varied by gender with a HR = 0.33 [95% CI, 0.11-0.99] for women (p for trend = 0.046) and a HR= 0.89 [95% CI, 0.44-1.78] for men (p for trend = 0.3). Data on OS is not yet mature, though the p trend among all patients with increasing PA is 0.02. CONCLUSIONS: Increased PA appears to be associated with DFS and OS among patients with stage III colon cancer. Follow-up data will be more mature at the time of presentation, as will analyses on the impact of PA on treatment-related toxicities No significant financial relationships to disclose.

Duke Scholars

Author Donna Niedzwiecki Biostatistics & Bioinformatics, Division of Biostatistics