The Significance Of Detecting Telomerase Activity And Nuclear DNA Quantitative Analysis In Exfoliated Cell In Stool For Diagnosis Of Colorectal Cancer

Objective: To explore the values of telomerase activity and nuclear DNA quantitative analysis in exfoliated cell in stool for diagnosis of colorectal cancer.Methods: To detect the telomerase activity and nuclear DNA quantitative in exfoliated cell in stool about 38 cases of colorectal cancer , 20 cases of noncancer by Polymerase Chain-based Telomeric Repeat Amplification Protocol ELISA. Also detect the telomerase activity in colorectal cancer tissues in 21 cases, paracarcinoma tissues in 17 cases, nomal tissues in 10 cases.Results:1. Exfoliative cytology in stool had a 55.26% sensitivity and 80% specificity for colorectal cancer in study. 2. The sensitivity of the telomerase activity in exfoliated cell in stool for colorectal cancer is 81.58%, specificity is 90.00%. 3. Telomerase activity in colorectal cancer tissues had a 90.48% sensitivity and 100% specificity in study for diagnosis ofcolorectal cancer. Positive rates in tumor tissues was distinctly higher than that in paracarcinoma and normal tissues. Among 19 cases who were detected positive in tumor tissues, 16 cases were also positive in exfoliated cell in stool. 4.The telomerase activity in exfoliated cell in stool for colorectal cancer had no significant difference in the different Dukes stages and in the positive or negetive lymph node metastases, but had a significant difference between histological differentiations. 5. DNA analysis of exfoliated cell nuclear in stool, DNA content, nuclear area, nuclear irregular index and percent of ≥ 5n cells in the stool were significant higher in colorectal cancer than in control group. The percentage of ≥ 5n cells were significant associated with histological grade.Conclusions: 1.Detection of telomerase activity in exfoliated cell in stool extreme-probabily plays an important role in diagnosis for diagnosis of colorectal cancer. 2. Telomerase may be an earlier event of malignant progression in colorectal cancer. It might be a parameter for diagnosis of colorectal cancer. 3. Some tumor cells exist in paracarcinomatissues far any distances from cancer tissues, therefor, surgeon should pay attention to complete excision. 4. DNA analysis of exfoliated cell in stool may provide an objective method of determining malignant grades and diagnosis of colorectal cancer.