A review of novel analytical diagnostics for liquid biopsies: spectroscopic and spectrometric serum profiling of primary and secondary brain tumours

With nearly 9,400 new cases of brain tumours diagnosed each year in the UK and over half of them resulting in death, the demand for a rapid, non-invasive diagnostic test permitting early detection is as vital and evident as ever. Brain tumours form when normal cells within the brain mutate, grow uncontrollably and form a mass. Brain tumours are stratified into increasing grades of malignancy determined by how they are likely to grow, the likelihood of reoccurrence and the likely best treatment, highlighted in Figure 1. Gliomas occur from the glial cells within the brain and central nervous system (CNS) are the most common primary brain tumour classified by World Health Organisation (WHO). Gliomas are often diagnosed late, are hard to treat and the prognosis is poor. Generally only 40% of patients with brain tumours are alive more than one year after diagnosis. Traditional treatment involves surgery, radiation therapy and chemotherapy but even with an extensive treatment plan survival is poor as symptoms are often diagnosed too late. The most common tumour types; astrocytomas, ependymomas and oligodendrogliomas have very different outcomes.