Digital PCR compartmentalization II. Contribution for the quantitative detection of circulating tumor DNA

Genetic markers are now widely used in the clinics, particularly in cancer patient management. Indeed, these tumor markers can help in the diagnosis and prognosis of the disease, and provide valuable information for treatment orientation in the context of personalized medicine. The presence of circulating cell-free tumor DNA (cftDNA) and thus of tumor markers in the blood can be considered to partly avoid the use of solid biopsies. The use of blood samples, as liquid biopsies, is less invasive and described as more representative of tumor heterogeneity. However, cftDNA can be found in blood in low proportion that can vary according to the nature and the progression of the tumor. For these reasons, the use of highly sensitive, specific and ideally quantitative methods for its detection are required. These requirements constituted until recently a technological limit, which now can be overcome thanks to digital PCR. This technology could now become a very efficient and non-invasive tool in oncology, complementary to conventional diagnostic techniques.