Diet and Physical Activity Intervention in CRC Survivors

Background - Colorectal cancer (CRC) incidence is increasing at an alarming rate in Hong Kong. A recent report concluded physical activity (PA) protects against colon cancer and foods low in dietary fibre, red meat and processed meat cause CRC. Yet, the influence of lifestyle factors on cancer outcome (i.e. recurrence and survival rates) in CRC survivors is largely unknown. Objectives \& hypothesis - Our study aims to evaluate the acceptability of two behavioural interventions for CRC survivors intended to improve cancer outcome and designed to (1) increase PA levels and (2) reduce consumption of a Western diet. The investigators hypothesize that the proposed interventions are (1) efficacious in changing the two targeted behaviours; and (2) acceptable to CRC survivors. Settings and methods - Phase 2 feasibility trial. Two hundred and twenty-four CRC survivors within 12 months of completion of cancer treatment and without evidence of persistent/recurrent disease will be recruited from four public hospitals in Hong Kong after informed consent. Subjects will be randomized in a 2x2 factorial design for the two targeted behaviours prescribed over 12 months. Primary outcome measure is whether the target levels of PA and dietary intake could be met at the end of intervention. Secondary outcome measures include: (1) magnitude of changes in PA level and dietary intakes; (2) rates and determinants of compliance; (3) facilitators and barriers to behavioural change; (4) measurement of theoretical constructs underlying PA and dietary interventions; (5) possible health benefits and side effects (PA-associated injury and nutritional deficiency) arising from the interventions. Outcome will be assessed at baseline, 6 months into intervention and then at 0, 6 and 12 months post-intervention. Impact - If proven feasible, our intervention programme would pave way for a large randomized controlled trial testing the effect of PA and diet on the treatment outcome of CRC.