The relevance of liquid biopsy in surgical oncology: The application of perioperative circulating nucleic acid dynamics in improving patient outcomes.

Background: Liquid biopsy is gaining increasing clinical utility in the management of cancer patients. The main components of a liquid biopsy are circulating nucleic acids, circulating tumour cells and extracellular vesicles such as exosomes. Circulating nucleic acids including cell free DNA (cfDNA) and circulating tumour DNA (ctDNA) in particular have been the focus of recent attention as they have demonstrated excellent potential in cancer screening, provision of prognostic information and in genomic profiling of a tumour without the need for repeated tissue biopsies. The aim of this review was to explore the current evidence in relation to the use of liquid biopsy in the perioperative setting and identify ways in which liquid biopsy may be applied in the future.

Methods: This narrative review is based on a comprehensive literature search up to the 1st of June 2020 for papers relevant to the application of liquid biopsy in surgical oncology, focusing particularly on the perioperative period.

Results: Recent evidence has demonstrated that perioperative liquid biopsy can accurately stratify patients' risk of recurrence compared to conventional biomarkers. Attention to the perioperative dynamics of liquid biopsy components can potentially provide new understanding of the complex relationship between surgery and cancer outcome. In addition, careful evaluation of liquid biopsy components in the perioperative window may provide important diagnostic and therapeutic information for cancer patients.

Conclusion: The rapidly evolving concept of the liquid biopsy has the potential to become the cornerstone for decision making around surveillance and adjuvant therapies the era of personalised medicine.