NCI is analyzing both serum and urine samples from a case-control study of colorectal adenoma conducted at the National Naval Medical Center in Bethesda, Maryland. Biofluids will be analyzed at Imperial College London. The study aims to: 1) assess the intra-individual variability in metabolomic profiles in multiple overnight urine collections; 2) assess concordance of metabolomic profiles in overnight urine collections with spot urine samples, which are more conducive for large etiologic studies; 3) identify individual metabolites in serum and urine related to individuals’ risk of colorectal adenoma; and 4) compare three different platforms for metabolomics analyses for investigating lifestyle factors and neoplasia risk. Metabolomic profiling, which involves the study of large numbers (400-800) of small molecules within biofluids, provides great promise for biomarker development since it incorporates exposure from diet, lifestyle, the environment, and genetics, among many other factors. The findings from this project could provide a major advance in our understanding of potentially modifiable risk factors for colorectal tumors, their underlying pathophysiology, and mechanisms.