Medicare Coverage For DCIS Biomarker Tests And Radiation Decisions

Why DCIS Creates A Radiation Dilemma

Ductal carcinoma in situ consists of abnormal cells confined to the milk ducts and is often described as stage 0 breast cancer. The clinical problem is that DCIS is not a single disease behaving in one way. Some cases may never become invasive; others carry a much higher risk of recurrence or progression.

“None of our clinical pathological tools can predict which class of DCIS is in the patient in front of us,” breast surgeon Dr. Patrick Borgen said.

For years, clinicians have estimated risk using factors such as age, tumor size, grade, surgical margins and tools such as the Memorial Sloan Kettering Cancer Center nomogram. DCISionRT adds tumor biology. The test measures seven proteins in tumor tissue and combines them with four clinical and pathological factors to estimate both recurrence risk and the potential benefit of radiation therapy.

That distinction matters. A prognostic test asks how likely the disease is to recur. A predictive test asks a different question: Is radiation likely to change that risk?

The Test Changes Decisions In Both Directions

The strongest argument for the test is not that it helps women avoid radiation. It is that it can move treatment decisions in either direction.

In a 2024 clinical utility study, physicians recorded their radiation recommendations before and after receiving DCISionRT results for 2,007 women at 63 sites. Recommendations changed in 38% of cases. Among 1,425 women initially recommended radiation, 41% had that recommendation withdrawn after testing. Among 582 women initially not recommended radiation, 31% were subsequently advised to receive it.

That makes this more complicated than an overtreatment story. A tool that identifies women who may safely skip radiation can also flag women whose tumors appear low-risk by conventional criteria but whose biology suggests radiation could help.

Borgen says his own practice sees the same two-way effect. That matters because he helped develop the older Memorial Sloan Kettering approach, which he now considers inadequate for the decisions doctors face today.

But changing decisions is not the same as improving outcomes. That distinction is at the center of Medicare’s objection.

Medicare Is Arguing About What Counts As Enough Evidence

The Molecular Diagnostic Services Program (MolDX), a Medicare contractor program administered by Palmetto GBA, reviewed 57 publications and concluded that the evidence does not yet convincingly show that current DCIS biomarker tests identify who can forgo radiation better than existing clinicopathologic tools.

Its draft policy points to several problems: limited direct comparisons with established risk tools, questions about how some Decision Score thresholds were analyzed, concerns about whether study populations represent Medicare patients, and gaps between clinical studies.

In plain English, MolDX is saying: Prove the new test adds enough information beyond what doctors can already get for free.

That is a legitimate scientific question. It is also a high-stakes standard if the information at issue can change whether a woman receives weeks of treatment.

PreludeDx argues the evidence has moved since the draft was written. A head-to-head analysis of 926 patients comparing the seven-gene biosignature against several clinicopathologic criteria was published two weeks after MolDX posted its proposal. It found that a majority of women classified as low-risk by traditional criteria were reclassified as high-risk by the test, and that those women had a 10-year recurrence rate of 21.4% without radiation versus 6.4% with it. Separately, NRG Oncology and the National Cancer Institute opened a randomized trial in April 2026 testing whether biosignature low-risk women can safely skip radiation.

The process adds another layer. At a July 2024 Contractor Advisory Committee (CAC) meeting, six of seven experts answered yes when asked whether sufficient clinical evidence supported biomarker testing to help determine which DCIS patients could forgo radiation. The committee was advisory, not binding, and MolDX’s later draft characterized the discussion as more unsettled.

Now the contractors are convening another advisory panel on October 13. That turns an evidence dispute into a governance question: When specialists and the coverage authority read the same record differently, who decides when the evidence is good enough?

Precision Medicine Still Has To Clear The Payment Gate

The federal government has already recognized DCISionRT in two other ways. The FDA granted it Breakthrough Device designation in 2025. The Centers for Medicare & Medicaid Services (CMS) granted it Advanced Diagnostic Laboratory Test (ADLT) status in 2023, a classification for certain sole-source tests that provide new clinical diagnostic information.

Neither recognition guarantees permanent Medicare coverage. Breakthrough Device designation is not FDA approval, and the ADLT decision is formally separate from a contractor’s coverage determination. But the mismatch is hard to ignore. One part of the government can recognize a diagnostic as innovative while another can conclude that its evidence does not justify coverage.

The contradiction became sharper this year. CMS and FDA created a new pathway designed to accelerate Medicare coverage of certain breakthrough devices. Still, they explicitly excluded in vitro diagnostic products, including laboratory tests, directing them back through existing Medicare coverage channels.

For PreludeDx President and CEO Dan Forche, the concern reaches beyond one test. Noncoverage, he said, “could be setting up to have a two-tier system” in which older women lose access while commercially insured patients may still get the information.

Vernon is not a Medicare patient, and that is part of the point. She had flexible insurance, the ability to travel, and enough information to find a test on her own. Precision medicine cannot become personalized only for patients who know what to ask for and can get to the answer.

Medicare will pay for radiation when it is covered and medically necessary. The harder question is whether its coverage system is keeping pace with the tools intended to determine when that treatment is necessary in the first place.