Ophthalmologist and Physician-Scientist
The Promise of the Liquid Biopsy Cancer Test

The Promise of the Liquid Biopsy Cancer Test

According to the most recent data published by Cancer, a journal of the American Cancer Society, approximately 1.7 million new cases of cancer are expected to be diagnosed in the United States in 2018 alone. The total number of lives claimed by the disease is estimated to be more than 600,000, with lung cancer, colorectal cancer and breast cancer ranking as the top three deadliest types of cancer.

With so many people and their loved ones affected in the United States alone, it is little wonder that cancer is considered to be the most widely feared illness in the developed world. People are eager for researchers to find a cure for this disease, and scientists studying the subject seem to be making progress with each passing year. The growth of Convergence in Healthcare has been particularly helpful in this regard, as the movement encourages experts from different backgrounds to work in deeply integrative teams to approach the issue of cancer treatment, diagnosis and prevention in new and exciting ways.

Among the most exciting developments in cancer treatment as a result of Convergence in Healthcare is the development of a test known as a liquid biopsy. Although it cannot cure cancer, this medical tool may do the next best thing: provide a simple, affordable and accurate way for physicians to diagnose cancer in its earliest stages, before the worst of its damage can be done and successful treatment of the illness is much more likely. The following is an overview of what the liquid biopsy test is, its benefits and its potential in the future.


What is the liquid biopsy?

A liquid biopsy is a preventive medical tool capable of detecting cancer before a tumor has spread from its point of origin in the body — a point when the chance of successful treatment is highest. In some cases, the test can indicate the presence of cancer before any physical symptoms develop. While there are different types of liquid biopsies designed for different uses in the diagnosis and treatment of cancer, a particularly promising test profiled by Science magazine in early 2018 is one that can identify up to eight forms of the disease. Known as the CancerSEEK test, this tool also helps physicians identify the location of cancer cells when the test indicates their presence in the body.

CancerSEEK works by measuring “levels of eight cancer proteins and the presence of cancer gene mutations from circulating DNA in the blood,” according to an online article from the Johns Hopkins University School of Medicine, where the test was developed. In the study published earlier this year, researchers reported the test identified 70 percent of the 1,000 patients already living with a cancer diagnosis who were tested. CancerSEEK was designed to specifically detect the presence of cancer in the colorectum, lung, breast tissue, esophagus, stomach, pancreas, liver and ovaries. These eight forms of the disease are collectively responsible for more than 60 percent of deaths caused by cancer every year.




What advantages does the liquid biopsy pose compared to other diagnostic tools?

Apart from being the latest development in the effort to catch cancer cells before they can cause deadly damage to the body, the liquid biopsy is also a less invasive, potentially safer screening method that could one day be a much more affordable way to diagnose the illness than traditional alternatives.

Many traditional cancer screening methods rely on medical imaging technology or surgical procedures to form a diagnosis. Various imaging tools typically used in screenings can expose patients to potentially harmful levels of radiation in the process of trying to determine whether or not cancer is present in the body, which can cause harm at the same time as it is trying to prevent it. Cancers diagnosed via a tumor biopsy, an invasive procedure requiring surgeons to remove tissue directly from the tumor itself, can be uncomfortable and, at times, require surgeons to extract bone marrow tissue to diagnose tumors in inaccessible areas using endoscopic methods and special needles, which subject patients to physical stress. Obtaining the results of tissue biopsies also often takes twice as long as the results of a liquid biopsy, which can be ready in as few as two weeks, in many instances.

The CancerSEEK liquid biopsy specifically is also likely to be more affordable in the future than surgical and imaging-based methods. Since CancerSEEK focuses on a small mutation panel of select biomarkers in the blood, it is much more economical to produce than tests which focus on a much wider range of DNA sequencing. The proposed cost of the test is currently under $500, which is less expensive than most other screening methods for single forms of cancer.


What kind of predictions has the scientific community made about the future of the liquid biopsy market?

While researchers still have a long way to go before a liquid biopsy can be considered a fundamentally reliable medical tool, enthusiasm for the test is clear. In October 2018, MarketWatch reported the value of the liquid biopsy market is projected to grow at a compound annual growth rate of 23 percent and to reach more than $2 billion by the year 2022. It has been the subject of panel discussions at major conferences such as MedCity CONVERGE and is already demonstrating more growth in use within the health sectors of Europe and Canada.

In the case of CancerSEEK, Johns Hopkins University states the test requires further testing on a large scale before it can be made publicly available. Only time will tell whether this pioneering diagnostic will play a key role in the fight against cancer.