Liquid biopsy in cancer using the Z-scan technique: A new approach to discover biomarkers in cancer

Abstract

Aim: Biomarkers have been broadly studied as a tool for the diagnosis and prognosis for different types of cancer. Z-scan is a kind of measurement technique that generates a nonlinear refractive index (n2). Today, Z-scan has been used in oncology to discriminate between solid tumors and to identify tumor circulating cell-free DNA in liquid samples. Materials & methods: According to the inclusion and exclusion criteria defined in this review, 35 articles were selected. Conclusion: The use of this technique for this kind of measurement will allow for a rapid and precise diagnosis of different types of tumor and may lead to better therapeutic approaches. Biomarkers are molecules, proteic or not, found in different body fluids or tissues. The study of these molecules makes it possible to diagnose several diseases in their initial stages, being fundamental for the control of pathologies. Z-scan is a nonlinear measurement technique capable of detecting some of these molecules. Its use has been considered for cancer diagnosis. This review provides pertinent information for better understanding this method and its importance for diagnostic medicine.