How to Appeal an Insurance Denial for Cancer Treatment

It can be a difficult decision to choose treatment after a cancer diagnosis. After a patient and their oncologist agree on a medication, the uncertainty of whether their insurance will pay for the treatment remains an obstacle. A denial can mean more paperwork, another round of reviews and a longer wait before treatment begins, leaving patients to wonder whether the medication their doctor prescribed is still an option.

In a study published in JAMA Network Open, researchers examined 4,952 second-level appeals for cancer medications denied under Medicare Part D between 2020 and 2024. Nearly 1 in 5 were decided in the patient’s favor, suggesting that some initial denials may have kept patients from appropriate treatments.

“I think one in five...is a signal that there was...medication that was appropriate for the patient that was being rejected,” said Youngmin Kwon, PhD, a postdoctoral research fellow in the Department of Health Policy at Vanderbilt University Medical Center and lead author of the study.

The odds of success depended on why the medication was denied in the first place. The findings reflect an issue in cancer care in which a medication may be supported by medical evidence, yet its financial coverage depends on navigating a complex appeals process.

Why Cancer Medications Can Be Denied

Cancer medications belong to a protected drug class under Medicare Part D, which means plans generally must cover all or nearly all drugs in that class. However, the protection does not guarantee every prescription will be approved for every patient.

Plans can still require prior authorization, in which a clinician must obtain approval before a medication will be covered, and they may impose other requirements to determine whether a treatment is medically necessary. A medication can appear on a plan’s list of covered drugs and still be denied for an individual patient, which researchers noted can be confusing for patients who believe their insurance already covers the treatment.

Prior authorization denials were often reversed on appeal, with 61.1% of second-level appeals involving them receiving favorable decisions. Kwon said the finding was concerning because the medications denied through prior authorization were prescribed for uses consistent with their approved indications.

Still, he noted that some of those successful appeals may have included documentation that wasn’t submitted during earlier reviews. An oncologist may need to provide biomarker testing results, imaging or other records showing that a patient meets the requirements for a particular treatment.

When Cancer Research Moves Faster Than Insurance Coverage

An oncologist may prescribe medications off-label, meaning for a condition or in a way that differs from what the Food and Drug Administration originally approved. Off-label prescribing is common in cancer care, particularly for patients with rare cancers or cancers that have stopped responding to standard treatments. A drug approved for one type of cancer may later show promise against another, but insurers may require additional evidence before agreeing to cover it.

“Sometimes science moves a lot faster than the law does,” said Joanna Duran, CEO and co-founder of Triage Cancer, a national nonprofit that provides free education and resources on the legal and practical challenges of a cancer diagnosis.

Insurers, she explained, may rely on existing coverage rules even as new evidence supports different uses of cancer medications.

Off-label and other non-medically-accepted uses made up the largest share of the study, with 68.9% of second-level appeals involving medications denied because their prescribed use was not considered medically accepted, a category that included off-label treatment. Only 16.5% of those appeals were successful.

Kwon said the lower approval rate may reflect legitimate uncertainty about the benefits of some off-label treatments, particularly when research is limited. However, about 88% of successfully appealed off-label medication cases involved uses backed by Medicare-recognized clinical references or peer-reviewed medical literature.

According to Duran, the core question oncology teams must answer is why the treatment is medically necessary, and published research supporting the treatment decision can be an important part of that case.

When Missing Paperwork Becomes a Barrier to Treatment

Administrative issues played a substantial role in creating barriers to treatment for patients. Among second-level appeals, 55.2% received unfavorable decisions because of clerical issues, a share that rose to 72.6% among appeals involving off-label medications. The clerical issues included missing medical records, insufficient documentation and failure to provide citations from scientific literature supporting the prescribed treatment.

Preparing an appeal often requires oncology teams to assemble an individualized package of evidence, Kwon explained. Depending on the medication, that might include a patient’s test results, a physician’s explanation of medical necessity, published research or recommendations from the National Comprehensive Cancer Network.

Medicare’s coverage rules also have different requirements for what qualifies as supporting evidence. A conference abstract or a study involving a different cancer, Kwon noted, may not meet the criteria reviewers use to determine whether an off-label treatment qualifies for coverage. Oncologists are responsible for understanding both the patient’s clinical needs and the evidence the plan requires.

The requirements can create additional barriers for patients. Duran said oncology teams often handle prior authorization requests and initial appeals before patients even realize their medication has been denied. When those efforts fail, patients may have to decide whether to pursue another appeal, consider a different treatment or seek financial assistance.

“Denials impede access to care,” Duran said. Patients who don’t pursue their appeal options, she explained, may be left figuring out how to pay for medications themselves.

What Treatment Delays Could Mean for Patients

The study examined appeals decisions rather than patients’ treatment outcomes, although Kwon said the potential consequences of delayed access shouldn’t be overlooked.

For some patients with advanced cancer, starting treatment quickly matters. A denial may require an oncology team to reconsider the treatment plan while waiting for another decision, and clinicians who anticipate coverage problems sometimes consider other therapies in the meantime. As a result, a patient may end up on a different treatment than the one originally recommended or face delays while an appeal moves through the system.

Kwon acknowledged that the available data don’t show how often treatment delays caused by denials lead to disease progression or worse outcomes. The study also could not determine every reason a particular appeal succeeded or failed, leaving questions about how consistently coverage criteria are applied. Because it captured only cases that reached the second level of appeal, it did not include patients who accepted an earlier denial, won approval at an earlier stage or never appealed at all.

The study’s blind spots (no patient outcome data, incomplete reasons for decisions, and no cases outside the second level of appeal) make it difficult to measure the full impact of insurance denials on people with cancer.

What Patients Can Do After a Cancer Medication Is Denied

Despite the complexity of the process, patients and caregivers have options to challenge a denial and seek coverage for their prescribed treatment.

“I think really the number one thing that we want patients and caregivers to know is that you do not have to take no for an answer,” Duran said. That holds regardless of what type of insurance a patient has.

The first step is understanding the coverage and why the medication was denied. For Medicare Part D, a patient or their representative can ask the plan to reconsider its decision. If the first-level appeal is unsuccessful, the case may go to an independent review entity contracted by Medicare.

Other plans have their own procedures and deadlines. Patients with private insurance, for example, may have access to an external review if an internal appeal fails, although eligibility and timelines depend on the plan and circumstances. When treatment is urgent, expedited appeals may also be available, and Duran said patients and providers should know how to request a faster decision rather than assuming they must wait through the standard process.

Throughout the process, Duran encouraged patients to stay in close contact with their oncology teams to find out whether an appeal has already been filed and what additional information may be needed. This includes asking whether the physician can provide a statement of medical necessity, relevant test results or scientific literature supporting the treatment.

“It’s very important for patients to be working with their healthcare teams to go through the full appeals process and to understand all of the steps of the appeals process,” she said.

What Could Make the Process Easier?

As insurers and healthcare organizations increasingly turn to artificial intelligence to manage administrative tasks, Kwon expressed concern about whether faster reviews would make it easier for patients to get treatment.

AI tools could help providers draft appeal letters, organize supporting evidence and spend less time on documentation. However, the same technology could also allow insurers to process denials more quickly.

“My concern is that ... once we have AI streamlining everything, you’re just gonna get faster rejection,” Kwon said.

He described a possible “AI arms race,” in which providers use automated tools to prepare appeals while insurers use similar tools to evaluate them. Greater efficiency may not resolve the underlying disagreements about medical necessity or whether a treatment has enough supporting evidence. Kwon said human oversight and transparency about how insurers use AI could become increasingly important as the technology is adopted.

Kwon also suggested reconsidering how much of the burden patients and providers should bear when seeking approval for treatments already supported by established evidence. One approach would be to reduce preapproval barriers for medications prescribed according to their FDA-approved uses and allow insurers to review certain prescribing decisions afterward. Such changes would require broader policy consideration, but Kwon said they could ease the administrative load on patients and oncology teams.

The findings highlight how access to cancer treatment can depend on the insurance review process even after a physician has prescribed a medication. Although a denial can delay access to treatment, patients may still have opportunities to challenge the decision through additional appeals.

“If you find yourself in a situation where insurance is denying coverage, and you don’t know what to do next, there are resources available,” Duran said.

References

1. Kwon Y, et al. “Second-Level Appeals of Denied Anticancer Medication Claims in Medicare Part D.” JAMA Network Open. Published July 23, 2026.
2. Vanderbilt Health News. “Study shows one-fifth of prescribed cancer drugs initially denied coverage in Medicare were overturned when reviewed.” July 24, 2026.
3. Triage Cancer. “Appeals.” https://triagecancer.org/appeals
4. Medicare.gov. “Claims, Appeals & Complaints.” http://www.medicare.gov/providers-services/claims-appeals-complaints

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