Sister chromatid exchange frequency in gastrointestinal system cancer patients

Purpose: Cancer is a disease whose cause has not been identified for certain yet. It isgenerally regarded as a multifactorial disease. However, recent studies have documented thatgenetic alterations are the primary cause of cancer etiology. One of the genetic study methodsis the Sister-Cromatid Exchanges. In our study, we aimed to demonstrate varieties of Sister-Cromatid Exchanges in patients with gastrointestinal carcinoma.Methods: We analyzed data from a cohort of 43 cases; 13 patient?s family members,15 control group and 15 patients with gastrointestinal carcinoma who were diagnosed andreceived treatment in Duzce University Medical School Hospital between May 2005 and June2006. 2 ml blood was collected by Na heparinized enjectors from patients and forwarded thesame day directly to the genetic labratory, and applied successively; culture, harvest, smear,Sister-Cromatid Exchange painting and analyses. We further evaluated the influence of age,sex, Sister-Cromatid Exchange, mithotic index, replication index and smoking on the results.Results: The average Sister-Cromatid Exchange rates were found as 16,06 for patientgroup, 5,23 for patients? family members group, and 3,51 for control group. The changesbetween patient group and the other two groups were statistically meaningful (p<0,01).Mithotic index levels were found as 5,4 for patient group, 7,15 for patient?s familymembers group, 9.0 for control group. Mithotic index values of patient group were found asmeaninfully lower than control group and patient?s family members group (p<0,05, p<0,01).The average replication indexes were calculated 1,39 for patient group, 1,70 forpatients?s family members group, 2,04 for control group. Replication index values of patientgroup cases were found significantly lower than patients?s family members group and controlgroup (p<0,01). Sister-Cromatid Exchange, mithotics index and replication index values wereconfirmed to be differring independant of age, sex and smoking.Conclutions: Sister-Cromatid Exchange is meaningfull in revealing the DNA damagein patients with gastrointestinal carcinoma. However, this study is not sufficient for geneticconsultation and in determining the risk for patients?s family members, futher studies areneeded and may provide meaningful statistical data. We conclude that such further studiesmay provide us a method applicable to early diagnosis of the disease or in scanning the riskypopulationKey Words: Sister-Cromatid Exchange, gastrointestinal system, carcinomas