Policy Meets Prognosis: Medicaid Expansion Related to Long-Term Cancer Survival

A study recently published in Cancer Discovery has linked Medicaid expansion in US states with better long-term survival in cancer patients, particularly among vulnerable populations and patients with high-risk cancers.^1,2

Key data points from the study include significant improvements in 5-year cause-specific survival in states that adopted Medicaid expansion (expansion states) across under-resourced patient populations, including those living in rural areas (difference-in-differences [DD], 2.55 percentage point [ppt]; 95% CI, 0.23–4.86) and high-poverty areas (DD, 1.54 ppt; 95% CI, 0.30–2.77). Such improvements were also observed in expansion state cancer cases associated with higher mortality, including pancreatic (DD, 2.60 ppt; 95% CI, 0.86–4.34), lung (DD, 1.32 ppt; 95% CI, 0.30–2.34), and colorectal cancers (DD, 1.31 ppt; 95% CI, 0.26–2.37).

In terms of overall survival (OS), non-Hispanic White and non-Hispanic Black patients in expansion states also saw higher OS compared with states that did not adopt Medicaid expansion (nonexpansion states), with DDs of 0.57 ppt and 1.05 ppt, respectively.

These findings contribute to the literature on Medicaid expansion’s impact on cancer outcomes by extending the scope of current evidence to encompass longer-term outcomes.

“Research has shown that Medicaid expansion can increase cancer screening prevalence, early-stage diagnosis, short-term survival, and now—according to our own analysis—[5]-year survival,” said Elizabeth Schafer, MPH, associate scientist at the American Cancer Society and study first author, in a press release.¹

What Is the Medicaid Expansion Policy?

In 2014, the Patient Protection and Affordable Care Act (ACA) began permitting states to expand Medicaid eligibility to adults with incomes up to 138% of the federal poverty level, with federally provided financial incentives for states that adopted the expansion.^1,3

To date, 40 states and the District of Columbia have adopted and implemented the expansion, while 10 states (Alabama, Florida, Georgia, Kansas, Mississippi, South Carolina, Tennessee, Texas, Wisconsin, Wyoming) have not.

What Was the Study’s Design?

This study utilized a difference-in-differences design, subtracting the difference between expansion states and nonexpansion states from 2007 to 2008 (pre-Medicaid expansion adoption) from the difference between expansion states and nonexpansion states from 2014 to 2015 (post-Medicaid expansion adoption).^1,2 Outcomes measured include 5-year cause-specific survival and OS. The quasi-experimental nature of the study likened pre-Medicaid expansion data and post-Medicaid expansion data to experimental and control groups, respectively.

Investigators obtained and analyzed data from the Cancer in North America dataset, including 1,423,983 cancer cases diagnosed in adults aged 18 to 59 years across 26 expansion states and 12 nonexpansion states at the time.

What Is the Clinical and Policy Relevance for Non-Expansion States?

While the study demonstrated favorable improvements in survival for patients in expansion states, it also raises concerns about the clinical implications for patients who reside in the remaining 10 nonexpansion states and potential state-level health inequities as a result of heterogeneous adoption across the US.

Health insurance facilitates access to care, preventive services, and disease treatment and management; however, prior research has shown disparities in cancer screenings and insurance coverage among US adults.⁴ Regarding clinical outcomes, an earlier study examining associations between state Medicaid income eligibility limits and cancer survival, presented at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting, found that patients who lived in states with lower income eligibility experienced worse cancer survival rates compared with patients who lived in states with higher income eligibility.

While not causative, the suggestion of long-term clinical benefits put forth by this study, especially for populations most in need, strengthen the evidence base for Medicaid expansion and should be leveraged in continued advocacy efforts and legislative discussions regarding expanding Medicaid to these states. Ultimately, the findings highlight the critical role of federal public health policies and programs in safeguarding health equity in the US.

“These findings underscore the importance of expanding Medicaid in the 10 remaining nonexpansion states and protecting expansion in the states that have already implemented it in order to improve outcomes for all individuals,” concluded Schafer in the press release.¹

REFERENCES:

1. Medicaid Expansion Linked to Improved Long-term Survival in Cancer Patients. News release. American Association for Cancer Research. October 8, 2025. Accessed October 10, 2025. https://tinyurl.com/d8mud5hh

2. Schafer EJ, Johnson CJ, Moraes FY, Han X, Zhao J, Jemal A. Association between Medicaid Expansion and 5-Year Survival among Individuals Diagnosed with Cancer. Cancer Discov Published online October 8, 2025:OF1-OF6. doi:10.1158/2159-8290.cd-25-1244

3. Status of State Medicaid Expansion Decisions. KFF. September 29, 2025. Accessed October 14, 2025. https://tinyurl.com/yck6yx7u

4. Zhao G, Okoro CA, Li J, Town M. Health Insurance Status and Clinical Cancer Screenings Among U.S. Adults. Am J Prev Med.2018;54(1):e11-e19. doi:10.1016/j.amepre.2017.08.024