Guardant Health Expands Cancer Detection Portfolio with Multi-Cancer Test and Quest Partnership

Guardant Health, a leader in precision oncology, has announced significant developments in its cancer detection portfolio, including a new multi-cancer detection test and a strategic partnership with Quest Diagnostics. These moves are set to reshape the landscape of early cancer screening and expand access to innovative diagnostic tools.

Shield Test Evolves into Multi-Cancer Detection Platform

Guardant Health's Co-CEO AmirAli Talasaz revealed plans to launch an expanded version of the company's Shield blood test in October. Originally developed for colorectal cancer screening, Shield will now offer multi-cancer detection (MCD) capabilities. This advancement builds upon the test's FDA approval as a primary screening option for colorectal cancer in adults aged 45 and older who are at average risk.

The Shield MCD test has already received FDA breakthrough device designation, highlighting its potential to address unmet medical needs. Furthermore, it has been selected by the National Cancer Institute for use in its Vanguard study, which aims to evaluate whether the benefits of multi-cancer detection screening outweigh potential harms and if such tests can help prevent cancer-related deaths.

Quest Diagnostics Partnership Broadens Access to Shield Test

In a move to increase the availability of its innovative diagnostics, Guardant Health has entered into a multiyear distribution agreement with Quest Diagnostics. Beginning in the first quarter of 2026, physicians will be able to order the Shield blood-based colorectal cancer test through their Quest accounts and electronic health records.

Quest Diagnostics, with its network of approximately 650,000 clinicians and hospital accounts, will play a crucial role in expanding access to the Shield test. As part of the collaboration, Quest's sales team will educate primary care physicians, obstetricians, and gynecologists about the test's benefits and applications.

Jim Davis, CEO of Quest Diagnostics, emphasized the potential of blood-based tests to reduce barriers to population screening, stating, "A blood-based test for colorectal cancer has the potential to reduce several barriers that prevent wider population screening." He added that Quest's scale could help increase early detection rates nationally.

Financial Projections and Future Outlook

Guardant Health has set ambitious financial targets for its Shield test, projecting revenue to exceed $500 million by 2028. This forecast underscores the company's confidence in the test's market potential and its ability to address the growing demand for non-invasive cancer screening methods.

As Guardant Health continues to process all Shield tests at its facilities, the partnership with Quest Diagnostics is expected to significantly enhance the test's market penetration. The collaboration between these two industry leaders marks a significant step forward in the accessibility and adoption of advanced cancer detection technologies.