Liquid biopsies are non-invasive blood tests that detect circulating tumour cells (CTCs), circulating cell free DNA which are fragments of tumour DNA and Exosomes and that are released into the blood from the primary tumour and from metastatic sites.The sequencing of the tumour genome helps in management of Cancer, identification of molecular target for targeted therapy and monitoring the course of the disease. Currently, tumour biopsy tissue, generally from the primary tumour, is used to determine molecular targets at a single time point, before treatment commences. These biopsies are painful, they are costly and, importantly, the process takes time. A tissue sample may not be a true representation of the molecular profile because of the complexities of tumour heterogeneity, both within a tumour and between a primary tumour and metastases. The liquid biopsies in this regard, may capture the entire heterogeneity of the disease. Also, tumour genotypes are notoriously unstable and prone to changes under selection pressure. Liquid biopsies offer serial samples in order to monitor tumour genomic changes in real time. This ensure doctors to choose the right therapy, chose molecules based on the targets seen and withdraw therapy if resistance develops. Also this gives chance to identify the cancer in an earlier stage, if the drug is not working so that unwanted drug toxicity can be avoided and look for newer targets suitable for treatment. So the patient gets the benefit of getting right therapy at the right time.
Liquid biopsies also helps in understanding of metastatic disease development and this in turn may help to identify signaling pathways involved in cell invasiveness and metastatic competence. CTCs have been the most studied. While these cells are relatively rare and require sensitive collection and enrichment technology, they provide information at both the genetic and cellular level. However, cell-free tumour DNA (cfDNA) is emerging as an effective alternative to CTCs, with the benefits of easier collection and analysis.
What is Liquid Biopsy?
A test done on a sample of blood to look for cancer cells from a tumor that are circulating in the blood or for pieces of DNA from tumor cells that are in the blood. A liquid biopsy may be used to help find cancer at an early stage. It may also be used to help plan treatment or to find out how well treatment is working or if cancer has come back. Being able to take multiple samples of blood over time may also help doctors understand what kind of molecular changes are taking place in a tumor.
Why should it be done?
Liquid Biopsy is an important part of Personalized Cancer treatment. Precision Oncology includes enhanced imaging techniques employed in Radiology and Pathology, detailed genetic testing and personalized genetic research, Nutraceutical diets, and Targeted Cancer therapy which includes innovative Surgical, Radiation and Chemotherapy techniques. Hence leading to reduced treatment side-effects and better treatment outcomes than standard treatment.
Better ability to pick heterogeneity / genetic variation in the tumors.
Are drugs administered working well can be known by tracking individual mutation.
Which drugs are not needed in present therapy by tracking mutations involved.
Monitor the status of cancer, in other words remission, potential recurrence before obvious signs of tumor and also start treatment early.
Identify new mutations developed which drive recurrence.
Lastly its less expensive and fast analysis.
How is it done?
Liquid Biopsy uses blood for obtaining Tumor DNA.
What does it show?
A Liquid Biopsy test checks blood for tumour DNA and shows
what mutations may be driving the cancer.
Concentration of tumour DNA in the blood stream and reveal how advanced the cancer is and
If your treamtent is benefitting you.
What Advantages Of Liquid Biopsy?
Tissue Biopsy not enough to establish the cancer status, Liquid Biopsy can be done to avoid repeated surgical biopsy.
If cancer is found in an area where surgical biopsy is not feasible or difficult, Liquid Biopsy can be done.
Cancer has spread to multiple sites and the primary site biopsy doesn’t give much information.
When cancer recurs after primary tumor has been surgically resected, Liquid Biopsy allows to find the presence of cancer and also the changes which have taken place.
Patient isn’t responding well to the treatment being given, Liquid Biopsy can reveal resistance to the therapy as well as find newer molecular targets, so targeted therapy can be administered.