what is CTC what is liquid biopsy

CTC or circulating tumor cells are cells that are detached from the primary tumor or from tumors that spread to other parts of the body (metastatic site) that gain access or enter the blood. 

Liquid biopsy is body fluid, but usually taken from the blood, that detect and analyze molecular substances or analytes such as ctc, dna, rna or vacuoles (exosomes). At present, liquid biopsy is not accepted way or standard procedure to confirm or use as a substitite for the definitive diagnosis of cancer. Liquid biopsy can be use to detect early signs of cancer, monitor the disease, help in determining progression of disease and determine the efficacy of treatment.