1 | INTRODUCTION
Remarkable progress in the overall survival of children with cancer over
the past several decades emphasizes the importance of long-term
follow-up care for survivors.1 Indeed, the late
effects of treatment, from secondary malignancies to cardiovascular
disease, affect every major organ system and demonstrate significant
heterogeneity in incidence based on underlying malignancy and specific
exposures.2 Clinical guidelines offer a framework for
disease surveillance after cancer treatment, yet lack of follow-up is a
significant barrier to early detection of late effects. The electronic
health record (EHR) sparks unique approaches to construct, maintain, and
leverage childhood cancer survivorship cohorts to optimize health care
delivery and as a platform for survivorship research. Ascertainment of
treatment exposures aids in risk stratification and identification of
survivors lost to follow-up.
Risk stratification of patients to determine appropriate levels of
follow-up care, both for the coordination with primary care providers as
well as the identification of high-risk survivors who would benefit from
regular subspecialist visits, facilitates judicious use of health care
resources to optimize patient outcomes.3 In the United
Kingdom, different levels of follow-up care were proposed based on
treatment exposures4 were later validated to ensure
appropriate capture of adverse effects.5 The British
Childhood Cancer Survivor Study (BCCSS) further refined the risk
stratification through the integration of underlying
malignancy.6 The introduction of novel targeted agents
and immunotherapy underscores the need for an adaptable system to
incorporate new risks for late effects from treatment. Albeit an
emerging field, there are associated cardiac,7renal,8 and endocrinologic9 adverse
effects during and shortly after treatment with these therapeutic
agents.10 In the coming years, new late effects from
these modalities will likely impact the care of adult survivors of
childhood cancer.
As knowledge of late effects risk improves, guideline recommendations
offer a framework for disease surveillance in order to mitigate further
complications. The Children’s Oncology Group (COG) regularly updates
long-term follow-up guidelines based on treatment exposure, including
radiation, surgery, immunotherapy, and each specific chemotherapeutic
agent.11 Furthermore, international efforts to
harmonize different recommendations across the globe provide another
layer for evidence-based survivorship care.12 Over the
past decade, published recommendations for
cardiomyopathy,13 breast cancer,14fertility,15,16, thyroid cancer,17and ototoxicity18 address major challenges for
survivors and inform delivery of appropriate care for early detection of
these late effects. Large, multi-institutional longitudinal studies,
such as the Childhood Cancer Survivorship Study
(CCSS),19offer a wealth of data to inform validated
risk prediction models for acute ovarian failure,20thyroid cancer,21 and cardiovascular
outcomes.22,23 Translation and implementation of these
recommendations and models into clinical practice, on an individual
patient and population health level, represent a tremendous opportunity
to optimize health outcomes in the digital age.
Long-term follow-up care of survivors enhances patient education and
early detection of late effects.24 Predictors of
suboptimal follow-up, such as age, insurance status, and race/ethnicity,
help identity at-risk populations.25 Studies of adult
cancer patients from rural areas reveal significant disparities with
regards to overall mortality26-28 and financial
toxicity29; however, there is a paucity of data for
survivors of childhood cancer. During active treatment, distance to the
cancer center is a considerable barrier,30,31especially for adolescents and young adults.32 For
high-risk survivors, distance to a comprehensive cancer center may also
influence their likelihood of receiving appropriate follow-up care.
The primary aim of this study was to harness an institutional cancer
registry, which follows the standards of and reports to the National
Cancer Database (NCDB),33 to construct a childhood
cancer survivorship cohort, integrate EHR and geospatial data to analyze
follow-up care patterns, and determine factors associated with
inadequate follow-up care. Risk stratification of survivors provides an
additional lens to prioritize survivors at risk for inadequate follow-up
care.