Cell-Free DNA and Cancer
According to the National Cancer Institute, cancer is among the leading causes of death worldwide. Worldwide cancer cases are expected to double by fifty percent from 2012 to 2030. The Cancer Moon Shoot is a project funded by NCI to advance and accelerate cancer research and make cure and therapies available for patients across the globe while detecting cancer at an early stage.
Currently, several methods such as biopsy and colonoscopy are used to detect cancers. These methods can fail to detect the early stages of cancer, and can be quite invasive. Acquiring the DNA through tissue biopsy can also be risky and unpleasant to the patient. However, a new methodology is being developed that relies on cell-free DNA (cfDNA). cfDNA is released into the blood stream when cells die - and cancer cells do die from time to time while a tumor is growing. This cfDNA can be detected by drawing blood plasma from patients during routine physical exams, or when a doctor suspects that a cancer is present. Explosive advances in the field of cancer research has given rise to an array of mutated DNA sequences (called biomarkers) that are indicative of cancer cells. DNA can also be chemically altered by a process called methylation, which also provides diagnostic biomarkers. Testing blood plasma for cancer-specific DNA sequences, or other biomarkers is being referred to as Liquid Biopsy, and represents the frontier of cancer diagnostics research. The dream is to someday be able to simply test patients for many or all cancers by taking a simple blood draw during routine examinations.
Cell-free DNA vs. Conventional Tissue Biopsy to Screen For Cancer
1. The process of using cell-free DNA found in the blood to screen for cancer is less expensive as compared to the course of having a surgical biopsy. It is also time-efficient and makes it possible to get the results in a short time.
2. Unlike the tissue biopsy which is limited to one tumor, the cell-free method identifies all the tumors in the body using genetic and epigenetic variations in the blood.
3. Analysis of the blood allows the oncology to determine which drugs work and which ones do not work for the individual mutations, which goes to ensure that you receive the right treatment. If the amount of mutated DNA appears to reduce during the treatment, then the treatment is working.
4. Another unique benefit of the test for circulating tumor cells is that it can be used to monitor cancer patients who are in remission. Through this, the pathologists would identify any chance of recurrence at an early stage. The cancer, should it return, would be easier to treat.
The cell-free DNA test has the potential to become a routine laboratory test done in patients, for early cancer detection as the price of cell free DNA extraction kit becomes cost effective and cancer biomarkers become more accurate in detecting cancer at an earlier stage.