LAUSR

3054 Background: We previously reported associations of pretreatment serum biomarkers with clinical outcomes in a cohort of advanced NSCLC patients that progressed on front-line therapy. This study aims to elucidate mechanisms underlying cancer cachexia/ pre-cachexia by evaluating relationships between baseline serum biomarker values and sequential changes in body weight, body mass index (BMI), and neutrophil/lymphocyte ratio (NLR) in NSCLC patients. Methods: We used Luminex immunobead assays to survey 101 protein biomarkers in sera from advanced NSCLC (n = 138) collected prior to their salvage regimen. Serial parameters associated with cancer cachexia included body weight, BMI, and NLR. Outcome variables (progression-free survival (PFS) and overall survival (OS)) were extracted with full IRB-approval. Biomarkers were evaluated as continuous variables with the cachexia surrogates using Pearson correlations, whereas associations of PFS and OS were accomplished with the Cox PH test. Results: High baseline values of BMI and low baseline NLR were associated with both OS and PFS (each p < 0.05), though weight failed to reach significance. PFS and OS were similarly associated with percent changes (relative to baseline) in weight (p < 0.01), BMI (p < 0.01), and NLR (p < 0.001). Thirteen biomarkers were found to be associated (p < 0.05) with baseline BMI values, including positive correlations with leptin, sol.VEGFR2, and c-peptide and inverse correlations with adiponectin, ferritin, ghrelin, IGFBP-1 and IL-8; fifteen biomarkers were associated with baseline NLR (all p < 0.05), including positive correlations with visfatin, insulin, and serum amyloid A and inverse correlations with IGF-II. Fifteen biomarkers were found to be associated (p < 0.05) in common with percent weight and BMI changes, including positive correlations with IGFBP-3 and inverse correlations with insulin, FGF-2, TNF-alpha, and resistin. Only prolactin and placental growth factor were found to be associated (p < 0.05) with percent change in NLR. Conclusions: A series of circulating protein biomarkers primarily connected with metabolic regulation and systemic inflammation/ acute phase response were found to be associated with cachexia/ pre-cachexia in NSCLC patients. Additional cohorts are currently being tested to verify these findings.