How Liquid Biopsies Promise To Improve Health Equity in Lung Cancer

Several years after the initial race to create a simpler blood test for cancer patients, where do we stand today and what does this mean for the daily race against the clock for curing lung cancer?

Dr. Kam Kafi, Avitia’s Chief Science Officer (CSO), is here to break down the use of liquid biopsy in lung cancer patients and its promising future.

What is Liquid Biopsy? 

Liquid biopsies are minimally invasive tests that are capable of detecting cancer cells or genetic material that are released into the blood from a tumor. 

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Source: https://directorsblog.nih.gov/2018/01/30/new-liquid-biopsy-shows-early-promise-in-detecting-cancer/ 

Collecting tumor tissue through biopsies is considered the gold standard for diagnosing and treating cancer. However, a tissue biopsy has limits due to tumor heterogeneity. That’s due to the differences between cancer cells within a tumor — thus the biopsy sample may not be representative of a tumor population's diversity. Further, tissue biopsies are painful to patients, and when a doctor takes a sample they miss the spot where the cancer is.

Blood tests could reduce the need for surgeons to cut tissue samples from suspicious lumps and lesions for diagnostic purposes. Thus, it is possible to reveal cancer lurking in places that needles and scalpels cannot safely reach. They could also determine what type of cancer is taking root and what treatment might work best to squash it. Procedurally, these tests are easily repeatable. That makes them attractive in monitoring patients who are diagnosed and treated — compared to traditional imaging methods are less sensitive and require repeated radiation exposure. 

With all that’s positive, liquid biopsy has limitations. What makes the search difficult is that certain types of cancer might not release a lot of DNA. It is like finding a needle in a haystack because the shed DNA from cancer represents just 0.1% of all cell-free DNA floating around in the blood. Although far from perfect, recent technological advances and a growing number of patients being tested are helping overcome these limitations. 

Impact of liquid biopsy on lung cancer

Despite a growing number of novel therapies, lung cancer is one of the deadliest cancers in the world. The National Cancer Institute estimates it will kill over 150,000 people a year. Part of the problem is there are a lot of different mutations that cause even its most common form. While the genetic profile of a tumor can tell doctors which treatment to prescribe, finding the mutation is an exercise in trial and error. The process looks like this:

Screen for the most common mutation, then try that drug. 

If it doesn’t work, screen again and try something else. 

It can take weeks or even months to find an optimal treatment — taking time that patients don’t have.

Currently, liquid biopsies are not used to primarily diagnose cancer. Rather, they are used to detect genetic mutations in the tumor that could suggest which drug should be used to treat the disease and monitor disease progression.

Historically, the first clinical application of liquid biopsy was in advanced Non-Small Cell Lung Cancer (NSCLC). These pioneer studies were followed by the advent and adoption of next-generation sequencing (NGS). This widened the spectrum of detectable mutations, leading to different opportunities. 

First, whenever a druggable alteration was found, matched therapy with specific medication might be offered. Second, certain present mutations or co-mutations could provide prognostic — as well as predictive information — helping oncologists decide on the next steps. This could include simply monitoring or adding additional treatments. Last, detecting tumor-specific genetic alterations at baseline, and measuring their variation during treatment, could be useful to monitor how effective early treatment worked. It could also help follow the disease course, allowing clinicians to track and treat mutations. This monitoring helps when we see the amount of cancer DNA in the blood go down, we definitely know we’re on the right track. However, if it starts coming back up, we have an early warning signal.

What’s next? Future health equity implications for cancer monitoring and screening

Over the past decade, liquid biopsy platform Innovation and development led to a growing number of regulatory approvals for blood-based tests. This furthered precision cancer care for patients with advanced disease. These tests increased their clinical application range in cancer treatment to now include monitoring cancer growth, detecting genetic mutations, identifying signs of relapse, and predicting sensitivity to immunotherapy. 

Over the next 5 years, liquid biopsy will be much more about enabling standards of care in oncology for new applications. This includes detecting molecular measurable residual disease (MRD), cancer screening, and treatment selection in earlier-stage disease. These factors can improve patient survival.

In 2020 alone, the FDA approved two comprehensive genomic profiling liquid biopsy tests — and the number of regulatory approvals continues to grow. 

Despite the increasing popularity of liquid biopsy testing in oncology care, their current use is limited to a handful of commercial offerings that are mostly available in the U.S. They are still expensive and not widely used in community care settings where the majority of patients are treated.   

What we need now is to leverage the existing infrastructure to enable access to liquid biopsies in-house at the point of care. This is exactly what we’re working on at Avitia. By adopting a distributed testing model, we provide community cancer centers with all the know-how and technology — AI, bioinformatics, reporting — to bring testing in-house so that they can provide cutting-edge testing to their patients using the infrastructure that is in place. 

Through this approach, we are able to reduce disparities in cancer testing by bringing down the price of liquid biopsies, speeding up turnaround times as samples don’t need to get shipped out, and ensuring greater patient data privacy as all the information stays within the institute. 

As technology becomes more affordable, it directly increases health equity by providing accessibility to larger populations that are treated by clinics that don’t have the same resources as top-tier hospitals in major cities. 

The growing adoption of this technology across the globe —  including North America, the Middle East, and South East Asia —  signals a brighter future for cancer patients around the world. 

To learn more about Avitia solutions and how you can bring quality NGS testing in-house, contact Avitia end be in touch: www.avitia.bio/contact

‍References used:

https://www.nature.com/articles/s41416-022-01777-8

https://www.scientificamerican.com/article/the-quest-for-cancer-detecting-blood-tests-speeds-up/

https://www.wired.com/story/fast-precise-cancer-care-is-coming-to-a-hospital-near-you/

https://www.nytimes.com/2016/06/05/health/liquid-cancer-test-offers-hope-for-alternative-to-painful-biopsies.html

https://www.theguardian.com/science/2017/jun/04/cancer-detection-liquid-biopsies

https://peterattiamd.com/maxdiehn/

https://ascopost.com/issues/october-10-2021/the-evolution-of-liquid-biopsy-in-cancer-care

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