A lung cancer blood test hit an FDA milestone. Another skipped the FDA.

What the FDA actually granted. Breakthrough Device Designation is a review program. It gives a company faster and more interactive access to FDA staff while a device is still investigational. It says nothing about whether the test works well enough to sell. Freenome is still running the prospective PROACT LUNG study (NCT06122077), and clearance is a separate decision that has not happened.

Sensitivity is the number the headlines used. In development data presented at the 2026 AACR annual meeting, across 363 lung cancer cases and 310 cancer-negative controls, SimpleScreen Lung reached an intended-use-population-adjusted sensitivity of 90.7%. Sensitivity is how often a test catches the disease when it is there. Catching nine of ten cancers from a standard blood draw would be a real result.

Specificity is the number underneath it. That 90.7% figure came at 50% specificity. Specificity is how often a test correctly clears people who do not have the disease, so 50% means half the cancer-free people tested also return a positive signal. Freenome reported the second operating point too: 80.4% sensitivity at 75% specificity. Every screening test trades one against the other, and a single accuracy percentage quoted on its own tells you which half of the trade someone chose to show you.

The comparison is not a CT scan. The proposed use is narrower than "a blood test for lung cancer." It targets adults 50 to 80 with at least a 20 pack-year smoking history who are not currently participating in guideline-recommended screening. For that group the recommended screening is an annual low-dose CT, and the pitch here is reaching people who are not getting one. A blood draw that pulls unscreened people into the system is a different proposition from a blood draw that replaces imaging.

This is Freenome's second FDA milestone of 2026, and they are not the same milestone. The FDA approved the company's SimpleScreen CRC colorectal test in July. That one is a decision to allow a test onto the market. This one is a decision to review a different test faster. Two milestones, two very different meanings, one company.

The FDA route is not the only route. On July 22, 2026, three weeks before Freenome announced its designation, Cizzle Bio began selling a different early lung cancer blood test to licensed providers in Dallas-Fort Worth and San Antonio. CIZ1B is an ELISA immunoassay run by OmniHealth Diagnostics, a CLIA-certified lab, as a laboratory-developed test. An LDT is validated by the lab that offers it rather than reviewed and cleared by the FDA, so a test can reach patients that way while a test on the FDA path is still years from a decision. Cizzle says it expects to add more CLIA lab partners in the coming months. The longest-running test on this route is not lung-specific: GRAIL’s Galleri, a multi-cancer test whose targets include lung cancer, has been sold by prescription as a laboratory-developed test since June 2021. An FDA advisory panel backed its approval application on September 23, 2026.

So the question is which route, not whether the FDA said something. Two lung-specific blood tests, two very different amounts of outside scrutiny. Neither is on a standard blood panel and neither replaces a low-dose CT. If a provider offers you a blood test for lung cancer, the useful question is where its performance numbers were reviewed: by the FDA, or by the single lab selling it.

Updated September 9, 2026. This post first ran under the headline "You still cannot order it." That was true of Freenome's SimpleScreen Lung and it still is. It was not true of lung cancer blood tests generally: CIZ1B had already been on sale in two Texas metros for a month when this published. The original framing treated the FDA milestone ladder as the only path to a patient, and missed the laboratory-developed-test route entirely.

Updated September 24, 2026. The first correction still undercounted. It called CIZ1B “a second early lung cancer blood test” and described the lab-developed route as if CIZ1B were its example, but GRAIL’s Galleri, which screens for lung cancer among more than 50 types, had been sold that way since 2021, five years before this post ran. The count above now refers to lung-specific tests, and the Galleri route is named.