Introduction: Cancer is the second biggest cause of death after heart disease and it is increasing hugely. According to WHO, this deadly disease killed almost 10 million people in 2020. The crucial point about cancer treatment, is early detection. Today, the most common ways to detect cancer are: CT scan (computerized tomography), MRI (magnetic resonance imaging), ultrasound, mammography, pap smear, PET scan (positron emission tomography) and solid biopsy. Each of them has its pros and cons. Some of them are invasive and harmful for the patients. Some kind of cancers are hardly detectable and these methods are not completely reliable in some cases.
Methods: Circulating tumor DNA (ctDNA) is a single or double stranded DNA fragment, released into the blood by cancerous cells. For using these fragments, a few milliliters of blood is needed and the method is called liquid biopsy. Analyzing these fragments can present a huge amount of information about the tumor. Solid biopsy has some limitations because the majority of tumors in the human body are heterogeneous and it would be difficult to choose the appropriate treatment for them.
Results: CtDNA can show the sites of primary and secondary tumors. It is promising for genotyping and also prognosis. By ctDNA it is possible to monitor genetic mutations, tumor progression, cancer development and treatment process.
Conclusion: In the near future ctDNA can change the patient journey completely and help the experts to choose the best treatments. Hence, it is extremely important to focus on new methods and use them to improve the patients life quality and health care systems.
Keywords: CtDNA, cancer, liquid biopsy, cancer treatment