COX2 and P27 Expression in Young Patients with Colorectal Cancer
BC Kenney, ME Robert, D Jain, KA Mitchell. Yale University School of Medicine, New Haven, CT
Background: Despite an overall decrease in incidence, colorectal cancer (CRC) rates are increasing in patients under 50. Specific pathologic, and now molecular, features have been described in these patients. Recent studies in CRC involving p27 and COX2 expression have shown potential for therapeutic use of COX2 inhibitors. We investigated CRC patients aged <40, <50, and 50-60, and analyzed morphologic data, MLH1 and MSH2 expression and p27 and COX2 staining among subgroups.
Design: Our database was searched for CRC resections in patients <40 (n=20), 40-50 (n=53) and 50-60 (n=89) from 1985-2009. Morphologic data, including tumor grade/differentiation, stage, size and lymph node status were determined from all available slides and reports. MLH1, MSH2, p27, and COX2 immunostains were done in patients <50 and graded on a binary or semi-quantitative scale. Statistical analysis was performed using one-way ANOVA and the f-test.
Results: Compared to reported rates in all CRC, patients <50 had less COX2 staining and greater incidence of MSH2 loss, but similar loss of p27 and MLH1.