Statistics and Its Interface
Volume 7 (2014)
We dedicate this special issue to Dr. Gang Zheng, a great colleague and dear friend to many of us.
Trends and patterns of childhood cancer incidence in the United States, 1995–2010
Pages: 121 – 134
Background: The American Cancer Society publishes Cancer Facts & Figures every year to provide estimated incidence rates and case counts for the current calendar year. Childhood cancer (children aged 0–14 with all cancer) incidence was also estimated and reported in Cancer Facts & Figures, but there is no report on patients in the 15–19 years of age or combined 0–19 years of age, or on major childhood cancers such as leukemia. There may be different effects of socioeconomic status and geography on childhood cancer in comparison to cancer in adults. Therefore, models used to predict cancer case counts for all patients may need to be modified to accurately evaluate and predict incidence rates of childhood cancers.
Methods: The original method was developed in 2007 to project the total cancer incidence counts reported in the Cancer Facts & Figures. This method requires first a spatiotemporal prediction across the extensive years of data since not all cancer registries have data for every year, and secondly a 4-year temporal projection from the most current data point to the current calendar year. Here we use this same process applied only to childhood cancer data. The generalized linear mixed effects model is applied to observed childhood cancer case counts reported to the North American Association of Central Cancer Registries over 1995– 2006 to predict case counts and incidence rates for every U.S. state and the U.S. total (for patients aged 0 to 19 and for major cancers among childhood). Covariates included in the model are measures of income, education, housing, urban/ rural status, health insurance coverage, smoking, obesity and cancer screening. Temporal trends and spatial distribution patterns are compared among childhood cancers for males and females.
Results: A total of 15,168 new cancer cases was projected for the 0–19 age group, with 10,032 childhood cancer cases younger than age 15, and 5,136 cases in the 15–19 age group, in the U.S. for 2010. There are more male cancer cases than female cases in all three age groups for most cancer sites. The order for the most common malignancies diagnosed in children differs by age group and sex. The study also identifies differences in the geograhic patterns at a small geographic area level by gender and temporal trends by gender and subsites of childhood cancer incidence.
Conclusions: The resulting set of predictions provides annual estimates for states that did not provide data at all, and projections ahead in time to the current calendar year for every U.S. state and the U.S. in total. These projections fill in the data gaps for recent years of diagnosis and state registries to provide complete count and rate estimates for childhood cancers for all states, regions, and the U.S. in total for the current calendar year.
childhood cancer, incidence, projection method, joinpoint regression, spatial pattern, temporal trend