Liquid biopsy is a fascinating and quickly evolving technology. Since the early 2000s, these tests have become increasingly complex, capable of gathering data on tens of thousands of genes across a patient’s DNA footprint at a time.
At the same time, liquid biopsies are becoming more and more prevalent in the research lab as well as the clinic, as new tests are approved for use by the United States Food and Drug Administration (FDA), and other world health authorities. Why? Because they can provide high quality, wide scope information without many of the downsides of traditional biopsies.
To many, liquid biopsies represent the future of oncologic testing.
But how will liquid biopsy technology improve in the coming years? Will they ever fully replace traditional solid tumor biopsies? And how can this technology evolve to fit some of the unmet needs of the oncology community? Before answering these essential questions, it’s important to take a step back to understand how liquid biopsies work, so we can take a look at how they may become even more useful in the future.
A brief history of liquid biopsy technology
In 1869, Thomas Ashworth observed cells in a patient’s bloodstream that closely resembled the cells in the tumor that he was studying. He concluded that the tumor must have shed those cells quite recently. In reflecting upon his discovery, he might have even imagined a time when technology was advanced enough to gather information about a tumor from the bloodstream of a patient.
Of course, the reality of current liquid biopsy tests is much more complicated than simply looking at circulating tumor DNA (ctDNA) in a patient’s blood. There are many other factors Ashworth was unaware of at the time of his discovery that make the task of creating a liquid biopsy test extremely complicated. Circulating tumor cells (CTCs) are often not homogeneous with the actual tumor cells in question, essentially making CTCs connected to, but not identical to, tumor cells. Also, only a limited number of CTCs survive for any significant amount of time in a patient’s bloodstream, making it difficult for analysts to figure out the missing pieces of the puzzle. Modern tests have been able to tackle some of these problems, but there is plenty of room for further improvement.
Unmet needs in liquid biopsy
Because of the level of sophistication that it takes to extrapolate information about a tumor from ctDNA and CTCs found in a patient’s bodily fluids, there are many ways that liquid biopsies can meet more of the needs of the medical community in the future.
For one thing, there remains a limited number of peer-reviewed studies that have collected conclusive information about the latest and most advanced liquid biopsy tests. This doesn’t mean that the tests don’t work or aren’t still useful, but it does mean that we may not be leveraging all of the information in these tests to the highest degree. One could easily imagine a worldwide database of cancer biology and biomarkers that could be cross referenced by an AI system to compare and contrast cases. The number of genes that these tests can sequence often goes far beyond our limited capabilities to recognize patterns in them. While we have a great understanding of many prevalent “red flags,” there may be intensely complicated patterns hidden deeper in the data.
Access to liquid biopsy tests and federal approval for them can also improve dramatically. While the FDA process is lengthy for approving tests and treatments due to their stringent safety standards and backlog of reviews, there is an unusual gap between the development of modern liquid biopsy tests and their approval. As the FDA catches up to biotech companies, more tests will be used, and we’ll be able analyze this additional data to better understand what additional utility these assays provide.
Additionally, insurance companies sometimes do not cover some types of liquid biopsy tests. While this differs company to company and insurer to insurer, making these tests more mainstream would certainly improve patient access to them. Liquid biopsy tech advancements won’t do anyone any good if they’re prohibitively expensive or only accessible in certain urban locations. Ensuring that the appropriate studies are run to demonstrate not only the clinical utility, but also the cost effectiveness of this approach is an important step forward for liquid biopsy.
How Personalis is helping
Personalis®, along with other cutting-edge oncology tech companies, are pushing the technological boundaries of what liquid biopsy tests can do. Our NeXT Personal™ assay has been developed to achieve the high sensitivity and specificity necessary to ensure disease is detected early and with high confidence. The ability to track not only known cancer variants, but also custom variants thought to be important to a specific treatment’s mechanism of action or patient’s response, provides unprecedented insights that will undoubtedly make an impact in future cancer care.
Our NeXT Liquid Biopsy™ test focuses on delivering the largest possible amount of genetic information for a clinical study, which will enable clinicians and drug developers to leverage more biological information in developing the new standard of care. We are invested in being a part of this larger cure, by providing tests and analysis that can help scientists understand larger oncologic patterns and trends. The more genes that future liquid biopsy tests can sequence, the better picture we will have of how these genes mutate and how these mutations and downstream biological phenomenon impact each other.
Both of these solutions represent only one facet of Personalis’ commitment to be a part of a larger oncologic solution. Through commitment to research, development, and state-of-the-art technology, we will continue to improve our liquid biopsy protocols, our solid tumor assays, and our clinical trial partnerships to advance what is possible in the field of testing and analysis.
Contact us to learn more about NeXT Personal and NeXT Liquid Biopsy.
All products described here are for Research Use Only and not for use in diagnostic procedures (except as specifically noted).