Back to 2026 Abstracts

---

Medicaid Expansion Is Associated with Decreased Mortality in Patients Diagnosed with Colorectal Cancer and Synchronous Liver Metastasis
*Julien Hohenleitner¹, *Rohin Gawdi¹, *David Hyman², *Lyudmyla Demyan³, *Angelina Lionetta⁴, *Oliver J. Standring¹, *Murtuza Hassan², *Steven M. Cohen², *Gerardo Vitiello², *Danielle K. Deperalta², Mark Talamini¹, *Sepideh Gholami², *Matthew Weiss^2
1General Surgery, Northwell Health, New Hyde Park, New York; ²Department of Surgical Oncology, Northwell Health, New Hyde Park, New York; ³Department of Surgical Oncology, Memorial Sloan Kettering Cancer Center, New York City, New York; ⁴Donald and Barbara Sucker School of Medicine, Hempstead, New York

Objective(s): The treatment of colorectal cancer with synchronous liver metastasis only (CRLM) requires a multidisciplinary approach, and equitable access to specialist care is essential. The 2010 Affordable Care Act increased the Medicaid income threshold to 138% of the poverty line. This study evaluates the impact of Medicaid expansion (ME) and its timing on treatment and survival in CRLM. Methods: The SEER 2022 database was queried for patients <65yo with CRLM between 2006-2019 (n=33,216). Patients lacking follow-up data or with extrahepatic metastases were excluded. States were grouped by ME timing: early (2011, n=20,213), On-Time (2014, n=4,699), Late (2016, n=2,605), or Never Expanded (NE, n=5,699). An event-study difference-in-differences (DiD) analysis was used to compare patient outcomes between ME and NE states, then stratified the groups by year of diagnosis relative to year of ME to adjust for improvements in treatment and survival over time. All-cause and disease-specific mortality were analyzed using Cox proportional hazards models clustered by state and adjusted for demographic and socioeconomic factors, with follow-up limited to 3 years. The chance of undergoing surgery was assessed with an event-study DiD Poisson regression model clustered by state. Results: Among 33,216 patients, most were male (60.1%), white (57.3%) and aged 55-59 (48.0%). Overall, 4,473 (13.4%) underwent liver metastasectomy. The prevalence of stage IV disease did not shift after ME. ME was associated with reduced 3-year (3yr) disease-specific mortality for all patients diagnosed 2-3(HR:0.95, p=0.02), 4-5 (HR:0.94, p=.005), and >6 years (HR:0.90, p<.001) after expansion. (Figure 1) ME was also associated with reduced 3yr all-cause mortality for patients diagnosed 4-5 (HR:0.96, p=0.03) and >6 years (HR:0.93, p<.001) after expansion. Chance of liver metastasectomy was not significantly changed for patients diagnosed after expansion. However, ME was associated with significant reduction in 3yr disease-specific mortality in patients undergoing liver metastasectomy diagnosed >1 year after expansion (HR: 0.71-0.85, all p<0.05) (Figure 2). ME was associated with reduced 3yr disease-specific mortality in patients treated with palliative chemotherapy diagnosed 4-5(HR:0.92, p=0.02), and >6 years (HR:0.86, p<.001) after expansion. (Figure 3). In patients treated with resection and adjuvant therapy ME was associated with reduced disease-specific mortality for patients diagnosed 2-3(HR:0.87, p=0.01) and 4-5(HR:0.90, p=0.01) after expansion. Finally, ME was associated with reduced disease-specific mortality in patients treated with neoadjuvant plus adjuvant therapy (HR:0.79, p=0.03). Conclusions:
ME was independently associated with significant reduction in mortality in patients with CRLM, particularly in those treated with liver resection and systemic therapy. These findings underscore the critical role of broad insurance access in improving surgical and oncologic outcomes.


Figure 1: Forest plot of Hazard Ratios for three-year all cause mortality across all patients in early, on-time, or late expansion states with CRLM vs non-expansion states, stratified by year diagnosed relative to the state's respective expansion year.