ASPO Abstracts
Trends in medical imaging use in children with central nervous system tumors
Category: Survivorship & Health Outcomes/Comparative Effectiveness Research
Conference Year: 2019
Abstract Body:
Purpose: We examined rates and types of medical imaging in children and adolescents diagnosed with central nervous system (CNS) tumors to understand imaging patterns during diagnosis and follow-up, and potential exposure to ionizing radiation.Methods: Our retrospective cohort study included children <21 years with an incident CNS tumor diagnosis (benign or malignant) recorded by regional tumor registries between 1996-2016 in 7 U.S. integrated health care systems. Children had to be enrolled in their health plan for >6 months before and after diagnosis and were followed for 10 years or until death, 6 months before a second cancer, plan disenrollment, age 21, or study end (12/31/2016). We used billing and diagnosis codes to capture imaging exams 1 year before and up to 10 years after diagnosis. We calculated imaging rates per child per month (PCPM) by exam type (computed tomography [CT], magnetic resonance imaging [MRI], nuclear medicine, ultrasound, angiography/fluoroscopy, and radiography), age at diagnosis, years of diagnosis, and tumor grade.Results: Among 727 children with CNS tumors, the median age at diagnosis was 11 years and 21% were diagnosed with malignant, high grade (III/IV) tumors. Imaging rates started to increase in the month before diagnosis and peaked in the month of diagnosis, with MRI exams being the most common (1.9 exams PCPM), followed by radiography (1.4 exams PCPM) and CT (1.0 exams PCPM). MRI use at diagnosis increased over time and was highest for cases diagnosed between 2010-2016 (2.1 exams PCPM), whereas CT rates were highest for cases diagnosed between 2003-2009 (1.1 exams PCPM) after which they declined. Radiography, MRI, and CT imaging rates were highest at diagnosis in children age ≤3 (2.8, 2.2, and 1.3 PCPM, respectively) and in children with malignant, high grade tumors (3.2, 2.8, and 1.8 PCPM, respectively). In the first year after diagnosis, MRI rates peaked at 3, 6, and 9 months and were the most common exam throughout 10 years of follow-up, and among younger age groups and children with malignant, high grade tumors. Conclusions: Imaging use is frequent in children with CNS tumors and has increased over time. MRI, which does not use ionizing radiation, is the most common type of imaging used in children with CNS tumors.
Keywords: pediatric oncology, surveillance imaging, brain tumor