Liquid Biopsy: Monitoring Cancer-Genetics in the Blood

“Tumour cells release circulating free DNA (cfDNA) into the blood, but the majority of circulating DNA is often not of cancerous origin, and detection of cancer-associated alleles in the blood has long been impossible to achieve. Technological advances have overcome these restrictions, making it possible to identify both genetic and epigenetic aberrations. A liquid biopsy, or blood sample, can provide the genetic landscape of all cancerous lesions (primary and metastases) as well as offering the opportunity to systematically track genomic evolution. This Review will explore how tumour-associated mutations detectable in the blood can be used in the clinic after diagnosis, including the assessment of prognosis, early detection of disease recurrence, and as surrogates for traditional biopsies with the purpose of predicting response to treatments and the development of acquired resistance.”


Liquid Biopsy: Monitoring Cancer-Genetics in the Blood

“Tumour cells release circulating free DNA (cfDNA) into the blood, but the majority of circulating DNA is often not of cancerous origin, and detection of cancer-associated alleles in the blood has long been impossible to achieve. Technological advances have overcome these restrictions, making it possible to identify both genetic and epigenetic aberrations. A liquid biopsy, or blood sample, can provide the genetic landscape of all cancerous lesions (primary and metastases) as well as offering the opportunity to systematically track genomic evolution. This Review explores how tumour-associated mutations detectable in the blood can be used in the clinic after diagnosis, including the assessment of prognosis, early detection of disease recurrence, and as surrogates for traditional biopsies with the purpose of predicting response to treatments and the development of acquired resistance.”


Tracking Resistance to Cancer Therapies Without Tumor Access


Clinicians would like to be able to monitor whether a cancer patient’s tumor has acquired a resistance mutation as a result of targeted therapy. Knowing early if resistance has developed would allow patients to switch therapies and to curb tumor growth. But taking repeated tumor samples is problematic for many reasons. Biopsies are invasive and some tumors are inaccessible. Another issue is that tumors are mosaics of many different types of cells that are constantly evolving—since biopsies take time in the clinic and only sample a small part of a tumor, they may also not be representative of what is going on with the biology of the entire tumor mass. Continue reading…


Tumor associated copy number changes in the circulation of patients with prostate cancer identified through whole-genome sequencing

Patients with prostate cancer may present with metastatic or recurrent disease despite initial curative treatment. The propensity of metastatic prostate cancer to spread to the bone has limited repeated sampling of tumor deposits. Hence, considerably less is understood about this lethal metastatic disease, as it is not commonly studied. Here we explored whole-genome sequencing of plasma DNA to scan the tumor genomes of these patients noninvasively…”