Correlation between patient′s age at onset of sporadic colorectal cancer and microsatellite instability in cancer tissues / 中国癌症杂志

Purpose:To investigate the relationship between inactivity of mismatch repair system in colorectal cancer (CRC) in Chinese patients and their age at onset of CRC.Methods:Genomic DNA extracted from colorectal cancer tissues and their normal colon tissues were subjected to analysis for microstallite instability (MSI) in six of DNA markers in 100 colorectal cancer patients.Results:Microsatellite instability positive (MSI + ) was detected in 46 out of 100 (46%) of CRC tissues, MSI + H in 18/100 (18%) and MSI + L in 28/100 (28%). The rate of MSI + in the CRC patients who are younger than 45 years old is higher than that in older patients (≥65 years ) ( P