Health Systems Strengthening Approach in the United States–Mexico Border Region Improved 5-Year Survival for Children With ALL

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The implementation of a collaborative program between North American and Mexican medical institutions to achieve sustainable, high-quality care at a public hospital in the United States–Mexico border region for children with acute lymphoblastic leukemia (ALL) has resulted in significant improvement in 5-year overall survival for these patients. According to the study’s findings, the 5-year overall survival for children with standard-risk and high-risk ALL improved from 52% to 82% and from 46% to 76%, respectively. Between preimplementation (2008–2012) and postimplementation (2013–2017), 5-year overall survival improved from 59% to 65% for the entire cohort, from 73% to 100% for standard-risk patients, and from 48% to 55% for high-risk patients.

Paula Aristizabal, MD, MAS

Paula Aristizabal, MD, MAS

The study, which was conducted by Paula Aristizabal, MD, MAS, and colleagues, was presented during the 2023 ASCO Annual Meeting.1 It was simultaneously published in JCO Global Oncology.2 Dr. Aristizabal is a pediatric hematologist-oncologist at Rady Children’s Hospital–San Diego and Associate Professor of Pediatrics in the Division of Pediatric Hematology/Oncology at UC San Diego and the Moores Cancer Center.

Improvements in treatment over the past 5 decades for children with ALL have resulted in cure rates reaching nearly 90% in high-income countries.3 However, in low-resource countries, cure rates for childhood ALL plummet to between 40% and 60% because of a multitude of factors, including health-care systems in these settings that are ill-equipped to manage cancer care for these patients.3

In this recent study, the investigators explored how international collaborative strategies may improve outcomes for children with leukemia in low- and middle-income countries, especially those that share a border with high-income countries.

Study Methodology

In 2013, in a partnership between North American and Mexican institutions, the researchers used a health systems strengthening model developed by the World Health Organization (WHO) called Framework for Action. It included domains in care delivery services, workforce, information systems, access to essential medicines, financing, and leadership and governance to implement a sustainable program with the goal of improving ALL outcomes at Hospital General in Tijuana, Mexico.

The researchers evaluated program sustainability indicators. They prospectively assessed clinical features, risk classification, and survival outcomes in 109 children with ALL at the hospital from 2008 to 2012 (before implementation of the program) and from 2013 to 2017 (after implementation of the program).

Key Results

The researchers’ approach led to a fully staffed leukemia service at the hospital with sustainable training programs; evidence-based data-driven projects to improve clinical outcomes; and funding for medications, supplies, and personnel through local partnerships. They found that the 5-year overall survival before and after implementation for children with standard-risk and high-risk ALL improved from 59% to 100% (P = 0 × 023) and from 48% to 55% (P = 0 × 031), respectively. All sustainability indicators significantly improved between 2013 and 2017.


  • A collaborative cross-border program between institutions in Mexico and California resulted in improving 5-year overall survival for children with standard- and high-risk acute lymphoblastic leukemia in Tijuana, Mexico, from 59% to 65% for the entire cohort, from 73% to 100% for standard-risk patients, and from 48% to 55% for high-risk patients.
  • The study investigators found that reductions in survival disparities in cancer outcomes were feasible with cross-border programs, especially borders that are shared between high- and low- and middle-income countries.

“By using a health systems strengthening approach, we improved leukemia care and survival in a public Mexican hospital in the U.S.-Mexico border region. The demonstrated increase in overall survival across a decade after the implementation of our program validates the use of the health systems strengthening models, as they are not only efficacious in improving clinical outcomes, but also serve as [a] financially and organizationally means of building sustainable capacity. Our model serves as an example for future international partnerships aimed at sustainably improving cancer outcomes in low- and middle-income countries. Future research should evaluate best practices in establishing global health collaborations with particular attention paid toward the individual circumstances that impact health-care delivery locally in each unique community,” concluded the study authors.

Clinical Significance

In an ASCO press briefing detailing the findings of this study, Dr. Aristizabal said that using a combination of twinning—the partnering of a center of excellence in a high-income country with a center in a low- and middle-income country to share knowledge, technology, and organizational skills—and the WHO Framework for Action model that is focused on sustainability was effective in reducing leukemia survival disparities. “Sustained improvements in cancer outcomes in low- and -middle-income countries are feasible with innovative cross-border programs, particularly in borders that are shared between a high-income country and a low-income country,” said Dr. Aristizabal.

“As I’ve heard Princess Dina Mired of Jordan say many times, ‘Your zip code should not determine if you survive cancer,’” commented moderator of the press briefing on these study findings, Julie R. Gralow, MD, FACP, FASCO, Chief Medical Officer and Executive Vice President of ASCO.

“And this is an example of children being so close in proximity and not having the same advantages. Your program focused on capacity building primarily, but in prior discussions, you’ve also told us that because of this partnership you were able to have drugs supplied by the Mexican Ministry of Health, which was not standard across the country. So that partnership also then involved the Mexican government in getting access to the drug as well, which I think is an important component. It takes lots of partners, not just a village, but lots of partners to achieve these outcomes,” said Dr. Gralow. 

DISCLOSURE: Funding for this study was provided by Rady Children’s Hospital San Diego and the Patronato Foundation. Dr. Aristizabal and Dr. Gralow reported no conflicts of interest.


1. Aristizabal P, Gomez Rivera R, Ribeiro RC, et al: Childhood leukemia survival in the US-Mexico border: Building sustainable leukemia care using health systems strengthening models. 2023 ASCO Annual Meeting. Abstract 1502. Presented June 3, 2023.

2. Aristizabal P, Rivera-Gomez R, Chang A, et al: Childhood leukemia survival in the US-Mexico border: Building sustainable leukemia care using health systems strengthening models. JCO Glob Oncol. June 3, 2023 (early release online).

3. Tandon S: Acute leukemia treatment in low- and middle-income countries: Is it time for tailored therapy? Cancer Res Treat 3:642-643, 2020.