Clinical characteristics of the study cohort.

Circulating tumor DNA (ctDNA) has high clinical potential in early cancer detection. The renal system and the liver are involved in clearing circulating cell free DNA (cfDNA) from the blood. Recent studies on mice show that inhibiting the liver’s ability to clear cfDNA results in elevated ctDNA levels in blood samples. Emphasizing the need for studies in humans exploring if markers of renal and liver function are associated with cfDNA and ctDNA levels in the blood. The present study investigates if cfDNA level, ctDNA level and ctDNA detection is affected in colorectal cancer (CRC) patients with clinical biomarkers indicative of low renal and liver function. We requisitioned standard laboratory tests of renal and liver function, measured within thirty days of curative intended surgery from 846 stage I-III CRC patients. For each patient, matching preoperative cfDNA and ctDNA data was available. We investigated the correlation between impaired renal and liver function and cfDNA level, ctDNA level, and ctDNA detection. The findings revealed that variation in renal and liver function in stage I-III CRC patients did not affect cfDNA level, ctDNA level, or ctDNA detection and that ctDNA test results remain stable over a wide range of renal and liver biomarker results.