Abstract
Circulating tumor DNA (ctDNA) in fluids has gained attention because ctDNA seems to identify tumor-specific abnormalities, which could be used for diagnosis, follow-up of treatment, and prognosis: the so-called liquid biopsy. Liquid biopsy is a minimally invasive approach and presents the sum of ctDNA from primary and secondary tumor sites. It has been possible not only to quantify the amount of ctDNA but also to identify (epi)genetic changes. Specific mutations in genes have been identified in the plasma of patients with several types of cancer, which highlights ctDNA as a possible cancer biomarker. However, achieving detectable concentrations of ctDNA in body fluids is not an easy task. ctDNA fragments present a short half-life, and there are no cut-off values to discriminate high and low ctDNA concentrations. Here, we discuss the use of ctDNA as a cancer biomarker, the main methodologies, the inherent difficulties, and the clinical predictive value of ctDNA.
Highlights
DNA circulates freely in the blood plasma of both healthy and sick individuals (Thierry et al, 2016)
This review will focus on the origin of cfDNA and Circulating tumor DNA (ctDNA) in body fluids, with an emphasis on DNAs from blood and plasma and their clinical utility as a marker in liquid biopsy to diagnosis and follow-up the treatment and recurrence of tumors
Liquid biopsy based on ctDNA is superior to previous plasma biomarkers with respect to sensitivity and clinical correlations (Sun et al, 2018)
Summary
DNA circulates freely in the blood plasma of both healthy and sick individuals (Thierry et al, 2016). DNA is present in human body fluids, its molecular origin remains poorly understood, and several possible sources have been proposed. The terminal differentiation of erythrocytes and keratinocytes is a source of plasma and urine DNA. In this case, the differentiation of erythroid cells resembles apoptosis (Lichtenstein et al, 2001). This review will focus on the origin of cfDNA and ctDNA (circulating tumor DNA) in body fluids, with an emphasis on DNAs from blood and plasma and their clinical utility as a marker in liquid biopsy to diagnosis and follow-up the treatment and recurrence of tumors
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
