Feasibility Outcomes of a Pilot Randomized Clinical Trial to Increase Cruciferous and Green Leafy Vegetable Intake in Posttreatment Head and Neck Cancer Survivors.

backgroundHigher intakes of cruciferous vegetables (CVs) and green leafy vegetables (GLVs) in observational studies are associated with improvements in survival and cancer-related biomarkers in patients diagnosed with head and neck cancer (HNC). These results have yet to be corroborated in a randomized clinical trial (RCT).

objectiveDetermine the feasibility of implementing a 12-week RCT to increase CV and GLV intake in posttreatment HNC survivors. DESIGN AND

participantsThis was a two-arm RCT conducted among 24 posttreatment HNC survivors. Survivors were recruited from a southeastern, National Cancer Institute-designated Comprehensive Cancer Center between January 2015 and September 2016.

interventionThere were two groups: (1) an experimental group (n=12) receiving weekly 15- to 30-minute telephone dietary counseling from a registered dietitian nutritionist stressing 2.5 cups per week CVs and 3.5 cups per week GLVs, and (2) an attention control group (n=12) receiving weekly 15- to 30-minute telephone dietary counseling from a registered dietitian nutritionist focusing on general healthy eating for cancer survivors. Participants completed a baseline survey, three 24-hour dietary recalls, phlebotomy, and anthropometric measures prior to randomization and at the end of the 12-week study period. The experimental group also completed weekly vegetable record recalls.

main outcome measuresPrimary outcomes included feasibility, recruitment, retention, adherence, and safety. Secondary outcomes included inflammatory markers and carotenoids. STATISTICAL ANALYSES PERFORMED: Descriptive statistics were generated for demographic, epidemiological, and clinical variables as well as the primary feasibility outcomes. Between- and within-group comparisons of mean serum cytokine and carotenoid levels were performed using appropriate statistical tests depending on their respective distributions for the purpose of generating preliminary effect sizes.

resultsOverall, 350 incident HNC cases were screened for eligibility, and 98 were eligible for study participation. Reasons for ineligibility and exclusion included deceased (n=93); wrong or inactive telephone numbers, or unable to be reached, or lost to follow-up (n=93); not meeting inclusion criteria (n=39); and too ill to participate (n=27). Of the 98 eligible HNC cases, 24 agreed to participate, for an enrollment rate of 25%. The most common reason for nonparticipation was distance (n=48), as participants were asked to report for two on-site assignments. The retention rate was 96%. Mean intervention adherence rates for weekly goals were 67% CV, 74% GLV, and 71% overall. Completion rate of weekly counseling calls was 90%. The experimental group reported an overall mean increase of 5.5 cups GLV and 3.5 cups CV per week from baseline intake, respectively. No significant between- or within-arm differences were observed for inflammatory markers or carotenoids.

conclusionA posttreatment intervention aimed at increasing CV and GLV intake in HNC survivors is feasible. A larger RCT is needed to assess the efficacy of this intervention on disease outcomes.