Liquid biopsy
A liquid biopsy, also known as fluid biopsy or fluid phase biopsy, is the sampling and analysis of non-solid biological tissue, primarily blood.[1] Like traditional biopsy this type of technique is mainly used as a diagnostic and monitoring tool for diseases such as cancer, with the added benefit of being largely non-invasive.
Although a liquid biopsy of circulating tumor cells has been validated and approved by the FDA as a useful prognostic method for various types of cancer,[2] its clinical implementation is not yet widespread.[3]
Types
There are several types of liquid biopsy depending on the condition that is being studied.
- In cancer studies, circulating tumor cells (CTCs) and/or cell-free tumour DNA (ctDNA) are collected.[4]
- In heart attack diagnosis, circulating endothelial cells (CECs) are sampled.
- In prenatal diagnosis, cell-free fetal DNA (cffDNA) is extracted from maternal blood. Amniotic fluid can also be extracted and analysed.
A wide variety of biomarkers may be studied to detect other diseases. For example, isolation of protoporphyrin IX from blood samples can be used as a diagnostic tool for atherosclerosis.[5] When studying the central nervous system, cerebrospinal fluid may be sampled instead of blood.[6]
How it Works
Unlike traditional biopsies, liquid biopsies remove the need for invasive surgeries and procedures by instead allowing medical professionals to test for signs of cancer from a simple blood-draw. As a result, biopsies are easier to perform, giving hope to many that they will lead to earlier diagnoses of cancers in patients.[7]
Liquid biopsies have been made possible by advances in sequencing the human genome since scientists and researchers can now detect genetic mutations of cancers. Researchers have found that unique cancer mutations can show up in microscopic fragments of DNA in a patient's blood. Tumor-related circulating-free DNA, RNA or proteins are released by tumor cells and circulate in the blood of cancer patients. Therefore, assays using these molecules can be used for early tumor detection, monitoring or detection of resistance mutations.[7][8]
References
- ↑ Crowley, Emily; Di Nicolantonio, Federica; Loupakis, Fotios; Bardelli, Alberto (9 July 2013). "Liquid biopsy: monitoring cancer-genetics in the blood". Nature Reviews Clinical Oncology. 10 (8): 472–484. doi:10.1038/nrclinonc.2013.110.
- ↑ Karachaliou, N; Mayo-de-Las-Casas, C; Molina-Vila, MA; Rosell, R (March 2015). "Real-time liquid biopsies become a reality in cancer treatment.". Annals of Translational Medicine. 3 (3): 36. doi:10.3978/j.issn.2305-5839.2015.01.16. PMC 4356857. PMID 25815297.
- ↑ Gingras, Isabelle; Salgado, Roberto; Ignatiadis, Michail (November 2015). "Liquid biopsy: will it be the 'magic tool' for monitoring response of solid tumors to anticancer therapies?". Current Opinion in Oncology. 27 (6): 560–567. doi:10.1097/CCO.0000000000000223.
- ↑ Heitzer, E.; Ulz, P.; Geigl, J. B. (11 November 2014). "Circulating Tumor DNA as a Liquid Biopsy for Cancer". Clinical Chemistry. 61 (1): 112–123. doi:10.1373/clinchem.2014.222679.
- ↑ Nascimento da Silva, Monica; Sicchieri, Letícia Bonfante; Rodrigues de Oliveira Silva, Flávia; Andrade, Maira Franco; Courrol, Lilia Coronato (2014). "Liquid biopsy of atherosclerosis using protoporphyrin IX as a biomarker". The Analyst. 139 (6): 1383. doi:10.1039/c3an01945d.
- ↑ Pyykkö, Okko T.; Lumela, Miikka; Rummukainen, Jaana; Nerg, Ossi; Seppälä, Toni T.; Herukka, Sanna-Kaisa; Koivisto, Anne M.; Alafuzoff, Irina; Puli, Lakshman; Savolainen, Sakari; Soininen, Hilkka; Jääskeläinen, Juha E.; Hiltunen, Mikko; Zetterberg, Henrik; Leinonen, Ville; Fiandaca, Massimo S. (17 March 2014). "Cerebrospinal Fluid Biomarker and Brain Biopsy Findings in Idiopathic Normal Pressure Hydrocephalus". PLoS ONE. 9 (3): e91974. doi:10.1371/journal.pone.0091974.
- 1 2 Gately, Gary."A revolutionary blood test that can detect cancer"CNBC,11 January 2016. Retrieved 19 May 2016.
- ↑ Karachaliou, Niki et al. "Real-Time Liquid Biopsies Become a Reality in Cancer Treatment" Annals of Translational Medicine 3.3, March 2015.Retrieved 19 May 2016.