Association of Medicaid Expansion with Diagnosis and Management of Colon Cancer

In March 2010, Medicaid expansion under the Affordable Care Act (ACA) was signed into law and has subsequently provided insurance to 10 million Americans living with incomes at or below 138% of the federal poverty threshold. Although initially intended to be nationally implemented, a Supreme Court ruling ultimately allowed individual states to decide whether to participate in Medicaid expansion. As of early November 2020, 38 states and the District of Columbia had affirmed their participation.¹ After expansion of Medicaid in these states, the literature has firmly established the law’s positive effect on healthcare for low-income families, demonstrating increased use of primary care, preventative care, and prescription medications, as well as reduced all-cause mortality.¹ In the surgical realm, and for surgical oncology in particular, Americans have benefitted from Medicaid expansion through increased screening, lower stage cancer at the time of diagnosis, and improved probability of optimal care for urgent and complex surgical diseases.^2-4

In “The association of Medicaid expansion with the diagnosis and management of colon cancer,” Hoehn and colleagues⁵ present novel and compelling evidence regarding the association between Medicaid expansion and improved colon cancer care in the US. Using the National Cancer Database (NCDB) and a quasi-experimental difference-in-difference model, the authors sought to determine whether Medicaid expansion had an impact on colon cancer staging, treatment decisions, surgical outcomes, and treatment facility characteristics. The authors report that Medicaid expansion was associated with more stage I diagnoses, stage I to III patients treated within 30 days of diagnosis, and stage IV patients receiving palliative care. Furthermore, Medicaid expansion was associated with fewer urgent and more minimally invasive operations, as well as treatment at integrated network programs. The key remaining question is, however: do these positive effects translate into improved cancer outcomes?

Hoehn and colleagues⁵ report no difference in certain short-term surgical outcomes—surgical margins status, length of stay, readmission, and mortality. The authors propose that colon cancer care has become increasingly standardized nationwide, and that patients with stage I–III colon cancer undergo essentially the same technical resection, regardless of institution. Therefore, earlier diagnoses may not affect these short-term outcomes, though we must be reminded that many of the postoperative complications tracked by NSQIP, such as anastomotic leak and surgical site infection, are not captured by the NCDB. Therefore, it is difficult to comment on individual patient-level surgical outcomes using NCDB’s dataset alone.

More importantly, we would argue, is understanding how Medicaid expansion may affect oncologic outcomes, both short- and long-term. Herein, the authors’ findings do provide evidence of improved outcomes for colon cancer patients on a public health level. First, earlier diagnosis and more timely treatment for stage I–III patients are both associated with improved overall survival^6,7; according to Surveillance, Epidemiology, and End Results (SEER) data, 5-year overall survival rates for stage I vs stage IV colon cancer are 74% and 5%, respectively.⁶ As such, detecting colon cancer at an earlier stage should improve long-term outcomes. Furthermore, urgent operations and delays >30 days after diagnosis are correlated with poorer long-term survival.⁷ Both of these clinical scenarios were less frequent for the Medicaid expansion states in Hoehn’s study population. Additionally, better access to palliative care for stage IV patients has been linked to higher patient satisfaction and quality of life.⁸ Lastly, fewer urgent procedures and more minimally invasive cases decrease resource use and length of stay.⁹ These are all “wins” that provide evidence of Medicaid expansion’s positive impact on the colon cancer patient population, even though current NCDB data are incomplete with respect to overall survival in the post-Medicaid expansion population.

To this point, an exciting future direction will be understanding the impact of Medicaid expansion on overall survival for colon cancer patients. Earlier this year at the American Society of Clinical Oncology annual meeting, Lee and colleagues¹⁰ presented age-adjusted mortality data from the National Center for Health Statistics and reported a decrease in age-adjusted cancer mortality in Americans <65 years of age living in Medicaid expansion states. Similarly, a study on Medicaid expansion’s impact on colon cancer screening, incidence and survival in Kentucky reported improved survival (as well as increased screening and early stage diagnoses) for Medicaid patients within the impoverished Appalachian region.¹¹ As noted above, national data specifically comparing overall survival for the colon cancer population before and after Medicaid expansion is not yet available, but it seems nearly certain that there will be a long-term survival benefit for colon cancer patients in expansion states that was not captured by the NCDB 30- and 90-day mortality rates in Hoehn’s study.

Finally, Hoehn’s article is extremely timely as the ACA is once again before the Supreme Court. Reports like “The association of Medicaid expansion with the diagnosis and management of colon cancer”⁵ are essential to inform the discussion with data-driven observations that describe the real-world impact of health policy. Hoehn and colleagues’ manuscript adds important data points to the picture, demonstrating improved timeliness of care for early stage colon cancer, fewer urgent cases, more minimally invasive cases, and better access to palliative care. Their findings build on previous studies that have pointed to Medicaid expansion as a predictor of improved access to surgical services and lower stage diagnoses in multiple malignancies.^12,13 Future studies should seek to elucidate Medicaid expansion’s long-term impact on overall survival and cost-effectiveness in the treatment of colon cancer.