Why you need to know about minimally invasive liquid biopsies to monitor your cancer
Why you need to know about Liquid Biopsies:
If you are interested in exploring personalised cancer medicine and how it can benefit you; you need to know about liquid biopsies.
Liquid biopsies also known as Cell-free DNA (cfDNA or ctDNA) tests, measure small fragments of DNA that are released into the blood by a shedding process from tumour cells that demonstrate mutated DNA.
Tumour cells from several cancers are known to release or shed circulating cell-free tumour DNA (ctDNA), which may contain identical mutations to those identified in a patient’s primary tumour.
Liquid Biopsies are drawn from a simple blood sample:
Release of ctDNA into the blood allows for a ‘liquid biopsy’ to be performed from a blood sample.
This removes the need for invasive procedures, such as biopsies through fine needle aspiration or surgical excisions, which may be risky for the patient or not possible due to the size or location of the tumour.
ctDNA testing may give an indication of the size of a tumour or the amount of cancer cells in the body, and importantly; serve as a non-invasive method monitor patient response to treatment and may alert doctors to early signs of recurrence or resistance.
One benefit of checking for ctDNA..
ctDNA can be used to check for residual cancer following treatment. It is a potential marker of residual cancer cells following surgery and may determine which patients will experience recurrence.
Radiology and imaging techniques can detect tumours approximately 7 – 10 mm in size. ctDNA is released by tumours around 20 times smaller than this, allowing for residual cancer cells to be detected much earlier.
The change of ctDNA levels in response to treatment has been observed across a range of tumour types, and some studies have found increased levels of ctDNA before or at the time of recurrence.
Another benefit of ctDNA is to monitor therapy and check for resistance to treatments. ctDNA testing provides an overview of all the different cells within a tumour.
Analysis can detect new molecular changes in the cells, which may provide an early indication of resistance to therapy.
For patients currently undergoing treatment, ctDNA testing may identify new treatment options.
Extra benefits ctDNA testing – early diagnosis and detection
Following further studies, ctDNA testing may potentially be used for cancer screening or early detection in the future.
The reason why it is important to track the Number of Cancer Cells in Real-Time:
1. Levels of ctDNA increase with disease progression and decrease in response to treatment.
2. ctDNA can more accurately reflect the real-time tumour size and burden than other cancer markers…
3. ctDNA levels over time can be used to monitor response to treatment, as shown in Figure 1.
Promising Blood Test Could Help to Predict Breast Cancer Recurrence: Source Time Mag
Currently available ways of tracking breast cancer cells in the blood are most useful in people with advanced cancer. In those conditions, cancer cells litter the blood with fragments of their DNA as they circulate throughout the body to seed new tumors in other tissues like the bone, liver and brain. But in early-stage breast cancer, these cells are, by definition, scarcer.
To address the problem, the research team, which included scientists at Arizona State University, the City of Hope, Mayo Clinic, and the Cancer Research UK Cambridge Institute, developed a new way to pick up elusive cancer DNA.
That could help guide treatment, by, for example, determining which patients require closer monitoring for recurrent growths. Because the sequencing identifies the genetic mutations contributing to the tumor, the test could also help doctors to decide which targeted drug therapies, which are designed to address specific cancer mutations, to prescribe for their patients.
Importantly, the test could help women whose tumors are effectively eliminated by their pre-surgery treatment to avoid an operation altogether since the blood test would reassure her and her doctor that no residual tumor DNA remained.