The kinetics of circulating cell-free DNA to predict the clinical efficacy of first-line chemotherapy in patients with metastatic colorectal cancer

Abstract

Abstract Purpose: The purpose of this study was to evaluate the value of circulating cell-free DNA (cfDNA) as a biomarker for predicting the efficacy of first-line chemotherapy in patients with metastatic colorectal cancer (mCRC).Methods: A total of 118 mCRC patients who received the first-line chemotherapy in Jiangsu Cancer Hospital from July 2018 to April 2020 were enrolled. CfDNA was quantitatively detected in plasma collected from colorectal cancer patients before and during the first-line chemotherapy. Correlations between cfDNA baseline levels and clinicopathological characteristics, cfDNA kinetics and progression-free survival (PFS) were then analyzed by SPSS25 (IBMCorph, Armonk, NY).Results: We found that elevated cfDNA baseline levels were associated with adenocarcinoma, liver metastases, rectal cancer, carcinoembryonic antigen (CEA) and lactate dehydrogenase (LDH) above upper limit of normal (ULN). Of note, patients with cfDNA levels＜24.13ng/ml and cfDNA kinetics (the ratio of post-chemotherapeutic cfDNA to cfDNA baseline levels) ≤ 1.215 after 4 cycles of chemotherapy had higher PFS. By multivariate COX model, we found that cfDNA levels and cfDNA kinetics after 4 cycles of first-line chemotherapy were independent predictive factors of first-line chemotherapy in mCRC patients.Conclusion: The cfDNA levels and the cfDNA kinetics in plasma after 4 cycles of first-line chemotherapy can be used as efficacy predictors for mCRC patients receiving first-line chemotherapy.