Liquid biopsy in tumors: opportunities and challenges

The emergence of non-invasive diagnostic techniques for tumors (1), such as liquid biopsy, marks a major step forward for humans on the road to conquering tumors. From the 2016 Food and Drug Administration (FDA) approval of the first liquid biopsy products based on EGFR gene mutations (2), by August this year, tumor mutation burden in blood (bTMB) was confirmed to predict the effectiveness of immunotherapy, and liquid biopsy has already made a big splash in the field of cancer treatment (3).