Zhu F, Ma J, Ru D, et al. - Researchers intended to confirm if the concentrations as well as integrity index of circulating cell-free DNA (cfDNA) in serum may be clinically valuable for the progression monitoring of colorectal cancer (CRC) cases. Participants were 76 primary CRC patients who had surgery, including 60 with chemotherapy and 43 with follow-up. From participants, serum samples were obtained. Experts identified long (247 bp) and short (115 bp) DNA fragments in serum via real-time quantitative PCR by amplifying the ALU repeats. Significantly higher median DNA integrity index (ALU247/ALU115) of serum DNA was detected in the preoperative group vs those in the postchemotherapy and the follow-up groups, while there was a significantly lower cfDNA concentration (ALU115) in the preoperative group relative to the postchemotherapy and the follow-up groups. Overall, experts concluded the potential promising utility of serum DNA integrity index (ALU247/115) as a candidate biomarker for prognostic prediction of CRC who received chemotherapy and during short-term follow-up.