Microsatellite Instability in the Management of Stage II Colorectal Patients
V. Strâmbu, D. Garofil, F. Pop, P. Radu, M. Brătucu, C. Iorga, R. Iorga, C. Pasnicu, A. Ion, F. PopaOriginal article, no. 6, 2013
Background: Up-to-date it is unclear whether stage II colorectalcancer patients should receive adjuvant chemotherapy.The presence of high risk features (T4, CEA 5 ng dl, lessthan 12 lymph nodes examined) is an indication forOxaliplatin based treatment. In their absence, there is noconsensus, 5 Fluorouracil regimens, or observation only beingequally recommended by oncologists. Microsatellite instabilityis associated with good prognosis in stage II colorectal cancerand also with poor response to 5 Fluorouracil and should beused as a predictive marker.Methods: We performed a prospective descriptive study on115 consecutive patients who received surgical resection forcolorectal cancer in our clinic during 2011 and 2012 using arisk stratification algorithm based on TNM staging, clinicopathologicand molecular markers.Results: From the 44 stage II colorectal cancer patients, 10cases were classified as high risk, in 26 cases we performedImmunohistochemical analysis that identified 8 patientswith low risk microsatellite instability phenotype, with noindication for adjuvant chemotherapy; 26 intermediate riskpatients received 5-FluoroUracil regimens.Conclusion: We believe that microsatellite instability testingprovides a useful tool in the goal of better characterizing patients with stage II colorectal cancer in matters of risk ofrecurrence and likelihood of benefit from chemotherapy.
