Abstract
U.S. breast cancer survivors (BCSs) are expected to increase to 4 million in the next 5-10 years. Cancer recurrence risk is highest in obese survivors. Inflammatory (Pro-I) biomarkers including C-reactive protein (CRP), Interleukins -3, -6, and -8 (IL-3, IL-6, IL-8), and Tumor Necrosis Factor (TNF)-α have been associated with cancer severity and recurrence. Nutritional interventions aimed at reducing inflammation may contribute to reduced recurrence risk and increase survival rates. However, studies have been limited to animal models. The goals of this one-year culinary-based intervention were to: 1) decrease Pro-I biomarkers and increase anti-inflammatory (AI) cytokines like IL10, by promoting AI food incorporation into BCS dietary routines; and 2) examine effects on potential cancer risk factors including body mass index (BMI) and circulating adipose stromal cells (ASCs).
A total of 153 BCSs was recruited. Overweight and obese women aged 18 or older, diagnosed with Stage 0-III breast cancer and at least 2 months post-systemic therapy at time of enrollment were randomized into Intervention (IG; n=76) and Control (CG; n=77) groups. CG received monthly nutritional brochures from the American Institute for Cancer Research. IG attended 6 monthly workshops (brief lectures on AI topics and chef-prepared food demonstrations), and received monthly tailored newsletters and telephone calls incorporating Motivational Interviewing techniques. At baseline, 6- and 12-month assessments, fasting serum was collected and assayed for Pro-I/AI marker and ASC levels; BMI was calculated from measured height and weight.
We examined trajectories of inflammatory biomarkers and whether these are affected by intervention group assignment and potential confounders. For each biomarker, we identified groups of trajectories from baseline to 12 months by modeling log-transformed longitudinal data using a discrete mixture model with censored normal distribution. Model fit diagnostics based on Bayesian information criterion, classification measures, and clinical judgement were used to determine the number of groups. Then, we investigated the association between trajectory group classification and covariates using chi-square test for categorical variables and ANOVA for continuous variables.
Participants' mean age at baseline was 56.6 (SD=9.4); mean BMI 32.4 kg/m2 (SD=4.9). There were no significant differences between groups on demographic variables. Intervention resulted in small changes in expected direction for CRP and IL-6 markers overall at 6 and 12 months, and for IL-8 only at 6 months. Between two and five trajectory patterns (linear or quadratic) were identified across all biomarkers. These patterns suggest that distinct BCS subpopulations that benefit differentially from nutritional interventions exist; therefore, suggesting tailoring strategies for future interventions. Future studies in larger samples are needed to provide more robust parameter estimation and facilitate generalizability of results.
Citation Format: Amelie G. Ramirez, Edgar Munoz, Dorothy Long-Parma, Alan EC Holden, Michael J. Wargovich. Trajectories of inflammatory biomarkers: A randomized longitudinal 12-months intervention promoting anti-inflammatory food consumption among breast cancer survivors. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B06.