TF and hepatocellular carcinoma: In addition, our result showed that the proportion of fragments with a length < 150 bp was obviously higher in HCC samples with high‐TF than in low‐TF and HBV samples, and selection of < 150‐bp length not only enhanced the TF to improve the clinical utility of ctDNA detection but also provided a new strategy for detecting CNV more accurately for HCC samples with lower CNV signals.