Impact of Socioeconomic Status on Timing of Relapse and Overall Survival for Children Treated on Dana-Farber Cancer Institute ALL Consortium Protocols (2000–2010)

Authors

  • Kira Bona MD, MPH,

    Corresponding author
    1. Department of Medicine, Boston Children's Hospital, Boston, Massachusetts
    2. Department of Pediatric Oncology, Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
    3. Harvard Medical School, Boston, Massachusetts
    4. Division of Population Sciences, Dana-Farber Cancer Institute, Boston, Massachusetts
    • Correspondence to: Kira Bona, Department of Pediatric Oncology, Dana-Farber Cancer Institute, 450 Brookline Ave, Boston, MA 02115.

      E-mail: kira.bona@childrens.harvard.edu

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  • Traci M. Blonquist MS,

    1. Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts
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  • Donna S. Neuberg ScD,

    1. Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts
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  • Lewis B. Silverman MD,

    1. Department of Medicine, Boston Children's Hospital, Boston, Massachusetts
    2. Department of Pediatric Oncology, Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
    3. Harvard Medical School, Boston, Massachusetts
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  • Joanne Wolfe MD, MPH

    1. Department of Medicine, Boston Children's Hospital, Boston, Massachusetts
    2. Department of Pediatric Oncology, Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
    3. Harvard Medical School, Boston, Massachusetts
    4. Division of Population Sciences, Dana-Farber Cancer Institute, Boston, Massachusetts
    5. Department of Psychosocial Oncology and Palliative Care, Dana-Farber Cancer Institute, Boston, Massachusetts
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  • Conflict of interest: Nothing to declare.

  • Grant sponsor: St. Baldrick's Foundation; Grant sponsor: National Palliative Care Research Center; Grant sponsor: Pablove Foundation; Grant sponsor: NIH P01; Grant number: 5PO1CA068484.

Abstract

Background

Population-based evidence suggests that lower socioeconomic status (SES) negatively impacts the overall survival (OS) of children with leukemia; however, the relationships between SES and treatment-related mortality, relapse, and timing of relapse remain unclear.

Procedure

We examined OS, event-free survival (EFS) and cumulative incidence (CI) and timing of relapse by community-level poverty for 575 children aged 1–18 years with newly diagnosed acute lymphoblastic leukemia (ALL) treated on consecutive phase III multicenter Dana-Farber Cancer Institute ALL Consortium Protocols between 2000 and 2010. Children were categorized into high- and low-poverty areas for the analysis using aggregate U.S. Census data linked to zip code.

Results

Children living in high-poverty areas experienced a 5-year OS of 85% as compared with 92% for those in low-poverty areas (P = 0.02); poverty remained marginally significant (P = 0.07) after adjustment for immunophenotype, age, and white blood cell count. There were no differences detected in EFS or CI relapse by poverty area. However, 92% of the relapses observed in children from high-poverty areas occurred <36 months from complete remission, compared to 48% of those in children from low-poverty areas (P = 0.008).

Conclusions

U.S. children with ALL living in high-poverty areas have a higher risk of early relapse when compared with those living in low-poverty areas despite uniform treatment. This may in part explain decreased OS observed in these children. This finding highlights disparities in childhood cancer outcomes by SES despite uniform treatment. Further investigations of the mechanistic pathways underlying this finding are needed.

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