Prognostic biomarkers in a series of stage II colon cancer.

3629 Background: Different clinico-pathological factors are used to define a group of patients with high-risk stage II colon cancer (CC) that may benefit of adjuvant treatment. Moreover, several molecular markers, such as microsatellite instability (MSI) and BRAF, have been widely investigated as prognostic factors. Recently a high stroma component (EMT+ subtypes) has also been associated with poor outcome. The aim of the study is to analyze the prognostic value of MSI, BRAF and tumor-stroma ratio in a prospective series of stage II CC patients. Methods: FFPE tissue from 432 stage II CC patients operated at Hospital Universitari de Bellvitge (1996 - 2006) were included in the study. MSI status was assessed by the analysis of 5 mononucleotide repeat markers (BAT-25, BAT-26, NR-21, NR-24 and MONO-27). BRAF V600E mutation was analyzed by single strand conformation polymorphism technique. Tumor-stroma ratio was analyzed by immunohistochemistry. Associations between molecular factors and clinical features were...