Somatic mutations of MMR gene are not often present in HNPCC and in sporadic RER+ colorectal cancers. Complete studies were made according to Bethesda and Amsterdam Criteria, and 35 patients belonged to the group with sporadic colorectal cancer, and 9 patients belonged to HNPCC group. The results of our studies showed that there is no significant difference between RER phenotype of HNPCC and sporadic cancer (p>0,05) in regard to microsatellite status. It can be a good indicator that there are so called 'susspected' on HNPCC among sporadic cancers which were not detected yet. The reason for this was an incomplete familial history of illness of patients and as such it was selected as sporadic cancer. Microsatellite analysis together with medical and familial history of illness can be a successful instrument for efficient HNPCC identification. However, successful solving of this problem lies in making an accurate diagnosis in comparative findings, which can be provided by genetic and clinical tests.
