Investigation of Efficacy Evaluation Comparison of cfDNA and CEA in Colorectal Cancer.

Background: To investigate the comparison of efficacy evaluation value for cell-free DNA (cfDNA) and CEA in advanced colorectal cancer.

Methods: A total of 40 patients with advanced colorectal cancer were enrolled in this study. By PCR Real-time, changes of plasma ALU247and ALU115 level as well as the cfDNA integrity (ALU247/ALU115) before and after chemotherapy were analyzed in patients with advanced colorectal cancer. Meanwhile, changes of CEA before and after chemotherapy were monitored to compare the efficacy evaluation value of cfDNA and the conventional CEA in the treatment of advanced colorectal cancer.

Results: After first-line chemotherapy, levels of ALU247, ALU115, and ALU247/ALU115 were significantly decreased (p < 0.05) in the respond groups from that of baseline, the same for CEA (p < 0.05). Levels of ALU115 and ALU247 and ALU247/ALU115 (p > 0.05) as well as CEA (p > 0.05) were not changed in stable groups compared with the baseline. In the progression group, however, levels of ALU247 and ALU247/ALU115 were significantly higher than baseline (p < 0.05), and CEA was also higher than that of baseline, but without statistical significance (p > 0.05). ROC curves showed that cfDNA integrity (ALU247/115) and CEA could be used as powerful indicators of outcome assessment.

Conclusions: Both cfDNA and CEA are closely related to the evaluation of the first-line chemotherapy for advanced colorectal cancer. The level and integrity of cfDNA are expected to be sensitive indicators for monitoring the efficacy of colorectal neoplasm treatment and earlier clues for tumor progression than CEA.