By Bill Alpert

Investors have waited with varying levels of patience for multi-cancer screening tests to lift off toward a targeted $30 billion to $50 billion in annual volume. Sales this year from the blood tests will be lucky to top $400 million.

But things are looking up, as more tests find their way into medical practice.

Not long after this year's end, regulators should rule on the marketing application of the first multi-cancer screening test — the Galleri product from industry pioneer Grail, which can flag 50 kinds of cancer by scouring a blood sample for DNA fragments shed from tumor cells.

A thumbs-up from the U.S. Food and Drug Administration would surely help Grail stock, which is down 20% this year, to $69, after a large British study missed its goal. FDA approval would also start the clock for Medicare to consider covering the test in 2028, under a law that Congress passed in February.

Medicare already covers Shield, a blood test from Guardant Health that's approved as a colorectal cancer screen. For no extra charge, patients and their doctors can receive Shield's findings on nine other cancers, including lung, ovarian and pancreatic. Guardant shares jumped 14% Wednesday, to $171, after the company said that the largest U.S. commercial health insurer, UnitedHealth, will cover the colorectal cancer screen for its 40 million members.

"It's actually scaling and getting adopted by physicians very strongly," Guardant's co-CEO AmirAli Talasaz told Barron's.

Guardant expects Shield revenue to rise from $80 million in 2025 to $192 million this year. The blood test appeals to the millions of patients uncomfortable with colonoscopies or even with stool-tests like Cologuard from the recently-acquired Exact Sciences unit of Abbott Laboratories.

Patients agree to share their medical records with Guardant in exchange for Shield's screening results on the nine other cancers. The company has screened over 100,000 patients, and when it has sufficient screening performance data on those cancers, it will seek FDA approval for additional cancers. Talasaz expects to reach one of those milestones "in the very near future."

Wall Street analysts project that Guardant's screening revenue will inflect sharply higher in 2028, then the new federal law calls for Medicare to start covering FDA-approved blood screens in those aged 68 and younger.

Revenue has also been rising smartly in Guardant's other businesses, which test blood for tumor DNA to help doctors choose treatments for diagnosed cancer patients, and monitor blood after treatment for signs of cancer recurrence. Total sales jumped 50% in the March quarter, and Guardant expects to report its first profit next year.

Exact Sciences began selling the Cancerguard multi-cancer blood test last year, under the same longstanding exemption from FDA approval used by Grail, for a test developed and processed at a single clinical lab firm. It detects 50 types of cancer.

Exact also licensed a blood-based colorectal cancer test called SimpleScreen CRC from Freenome, a Brisbane, California, startup that plans to go public by merging into the special-purpose acquisition company Perceptive Capital Solutions, after the SPAC's shareholders vote on July 9. Freenome has an application before the FDA to market the colorectal cancer blood screen.

The successful genomics company Natera is also on track to submit an marketing application for its colorectal cancer blood screen in this year's September quarter. On its last earnings call, Natera said the screen is finding precancerous growths more successfully than other blood screens.

Multi-cancer DNA tests vary in their sensitivity to very early stage cancers from certain tissue, like the prostate and breast. Caris Life Sciences developed a screen that performs a deeper analysis of blood-borne DNA to detect those early stage cancers. On Wednesday, the company announced the availability of the Caris Detect blood test, which it says is more sensitive at finding early cancers than other blood tests.

Guardant's Talasaz says the DNA blood screens will also be able to detect early signs of diseases other than cancer. The company already has medical data on over a million patients.

"We are putting together a database now of about 500 diseases," Talasaz says.

Write to Bill Alpert at william.alpert@barrons.com

This content was created by Barron's, which is operated by Dow Jones & Co. Barron's is published independently from Dow Jones Newswires and The Wall Street Journal.

Corrections & Amplifications

The Exact Sciences unit of Abbott Laboratories offers two blood-based cancer tests: the multi-cancer test Cancerguard and the colorectal cancer test SimpleScreen CRC. An earlier version of this article published on July 1, 2026 confused aspects of the two tests.