Blood-Based Biomarker Tests for Colorectal Cancer Screening

Core Concepts

Blood-based biomarker tests may revolutionize colorectal cancer screening, potentially replacing colonoscopies in the future.

Abstract

The content discusses the potential approval of blood-based biomarker tests for colorectal cancer (CRC) screening by US regulators. Various companies, including Guardant Health, Inc, CellMax Life, Freenome, and Exact Sciences, are developing blood tests for CRC. The shift towards noninvasive tests could impact the prevalence of screening colonoscopies. However, past disappointments with CRC blood tests and the necessity of follow-up diagnostic procedures post-positive results are highlighted. The article also delves into the challenges of gaining FDA approval, Medicare coverage, and USPSTF recommendations for CRC blood tests.

Stats

Guardant's Shield blood test for CRC
CellMax Life, Freenome, and Exact Sciences developing blood tests
Grail's Galleri test for 50 types of cancer
CellLife Max's blood test sensitivity of 92.1% for CRC
Guardant's blood test sensitivity of 83% for CRC

Quotes

"They're coming, and they will be increasingly widely used." - David A. Johnson, MD
"A blood test for cancer screening has been the 'holy grail'..." - David F. Ransohoff, MD
"The best intent for screening is prevention of cancer, not detection of cancer." - David A. Johnson, MD

Key Insights Distilled From

CRC Blood Tests: A Future Without Screening Colonoscopies?

by Kerry Dooley... at www.medscape.com 04-05-2023

https://www.medscape.com/viewarticle/990465

Deeper Inquiries

How might the introduction of blood-based CRC tests impact current screening practices?

The introduction of blood-based CRC tests could potentially revolutionize current screening practices for colorectal cancer. If these tests prove to be highly sensitive and specific, they could offer a more convenient and noninvasive alternative to traditional screening methods like colonoscopies. Patients who are averse to colonoscopies or face barriers to accessing them may find blood tests more appealing, leading to increased screening rates. Additionally, the availability of multiple FDA-approved blood tests could provide clinicians and patients with a variety of options to choose from, catering to individual preferences and needs. However, the shift towards blood-based tests may require significant changes in healthcare systems and patient education to ensure widespread adoption and effectiveness.

What are the potential drawbacks of phasing out colonoscopies in favor of blood tests for CRC screening?

While blood-based CRC tests offer promising benefits, there are several potential drawbacks to consider when phasing out colonoscopies in favor of these tests. One major concern is the possibility of false positive and false negative results associated with blood tests, which could lead to unnecessary follow-up procedures or missed diagnoses. Colonoscopies not only serve as a screening tool but also allow for the removal of precancerous polyps, offering a preventive aspect that blood tests lack. Additionally, some patients may prefer the comprehensive evaluation provided by colonoscopies, which can detect other gastrointestinal issues beyond CRC. The transition away from colonoscopies would also require significant changes in healthcare policies, reimbursement systems, and physician training to ensure the effectiveness and safety of blood-based screening programs.

How can the medical community address the challenges of false positive and false negative results associated with CRC blood tests?

Addressing the challenges of false positive and false negative results associated with CRC blood tests requires a multifaceted approach from the medical community. Firstly, ongoing research and development are essential to improve the accuracy and reliability of blood-based tests through rigorous clinical trials and validation studies. Healthcare providers must also prioritize patient education and informed decision-making, ensuring that individuals understand the limitations and potential risks of blood tests compared to colonoscopies. Implementing clear guidelines and protocols for follow-up procedures in cases of positive results can help minimize unnecessary interventions and ensure timely diagnostic evaluations. Continuous monitoring and evaluation of blood test performance, along with feedback mechanisms for healthcare professionals, are crucial for maintaining quality assurance and optimizing patient outcomes. Collaborative efforts between researchers, clinicians, policymakers, and patient advocacy groups are essential to address the challenges associated with false results and enhance the overall effectiveness of CRC screening programs using blood-based tests.