This study comprehensively characterizes transrenal DNA (trDNA) in patients with hepatocellular carcinoma (HCC), using HBV DNA as a representative marker. The authors compared fragment size distributions, end motifs, and mutation detection rates between urine and plasma cfDNA. The findings on shorter HBV trDNA fragment lengths in HCC patients and the high concordance of mutation detection between urine and plasma are compelling. The manuscript is well-structured and offers significant insights into urine-based liquid biopsy.