The Correlation Analysis Of The Concentration Of Plasma Cell Free DNA Of Patients With Colorectal Cancer Between Clinical Features

Background and ObjectiveColorectal cancer is one of the malignant tumors with high morbidity and mortality,in the early stage,there is no obvious symptoms,the majority of patients diagnosed in the late stage,about 20% of patients had a distant metastasis at the time of initial diagnosis,5-year survival rate was only 11.7%.Early diagnosis of colorectal cancer is very important for detecting,treating and improving the prognosis of patients in time.However,there are still many difficulties in the early diagnosis of colorectal cancer.Serum tumor marker detection is one of the most common methods for early detection of colorectal cancer,but its sensitivity and specificity are not so ideal.In recent years,plasma cfDNA plays an important role in early diagnosis of colorectal cancer as a new tumor marker.In this study,we recruits patients with colon polyps,colon cancer and rectal cancer,to analyze the differences of plasma cfDNA levels between different stages of colon cancer and the relationship between the clinical features of colon polyps and colorectal cancer and plasma cfDNA level.In order to provide a basis for the applications of plasma cfDNA in early screening and accompanied diagnostic of colorectal cancer.Materials and MethodsThis study recruits patients with colon polyps,colon cancer and rectal cancer,we collecting the clinical data of the patients,and collecting the peripheral blood samples from patients,isolation and extraction of plasma free DNA,quantitative plasma free cfDNA concentration.To analyze the differences of plasma cfDNA levels between different stages of colon cancer and the relationship between the clinical features of colon polyps and colorectal cancer and plasma cfDNA level.SPSS 22.0 and GraphPad Prism 5.0 software were used for statistical analysis.The statistical level was ? = 0.05.Results1.Plasma cfDNA concentration in colorectal cancer patients was significantly higher than that in patients with colonic polyps(P <0.05).There was no significant difference in plasma cfDNA concentration between patients with inflammatory / proliferative polyps,non-advanced adenomas and advanced adenomas(P> 0.05).There was no significant difference in plasma cfDNA concentration between colon cancer stage I-II and stage III(P> 0.05).Colon polyps patients' age,gender,pathological type,quantity,size and the plasma level of cfDNA is no significant difference between groups.2.There was no significant difference in age,sex,pathological type,quantity and size between plasma and plasma cfDNA levels.3.The plasma cfDNA concentration in colorectal cancer patients was significantly higher than that in rectal cancer group(P <0.05).There was no significant difference in cfDNA concentration between left colon cancer group and left colon cancer group(P> 0.05).Colorectal cancer patients had no significant difference in age,sex,tumor staging,gross type,and plasma cfDNA levels.4.There was no correlation between plasma cfDNA level and tumor TNM stage,which was positively correlated with the logarithm of tumor volume(r = 0.474,P <0.01)ConclusionPlasma cfDNA levels have an upward trend in different periods from the early colonic benign lesions to advanced colonic cancer,and it can help to diagnose colon cancer,and can indirectly reflect the tumor burden in patients with colorectal cancer.