Study Finds Both the Number of Childhood Cancer Survivors and the Prevalence of Morbidity Are Increasing
Researchers investigating the prevalence of childhood cancer survivors and the population-level burden of morbidity in these survivors have found that although the number of childhood cancer survivors has increased by nearly 60,000 since 2005, the majority of those who have survived 5 or more years beyond diagnosis may have at least one chronic health condition. The results from their study, said the researchers, call for future research focused on decreasing the morbidity burden and incorporating effective clinical models of care coordination and rehabilitation to reduce the morbidity burden and optimize the health-related quality of life, physical and neurocognitive functioning, and mental health of survivors of childhood cancers. The study by Phillips et al is published in Cancer Epidemiology, Biomarkers & Prevention.
Study Methodology
The researchers used data on the incidence and survival from cancers diagnosed in individuals 19 years and younger from 1975 to 2011 in nine Surveillance, Epidemiology, and End Results (SEER) registries. Data from the Childhood Cancer Survivor Study (CCSS) cohort on a variety of potential adverse and late effects from cancer treatment from over 14,000 long-term survivors of childhood cancer diagnosed between 1970 and 1986 at the age 19 or younger were included to provide as similar a population to that in SEER as possible. Survivors with germ cell tumors and benign or borderline brain and central nervous system tumors were excluded from the study.
The scientists first obtained estimates of the probability of each measure of morbidity from the CCSS cohort and then multiplied these estimates by the relevant number of survivors in the United States estimated from the SEER data.
Study Findings
Based on their findings, the researchers estimated the number of childhood cancer survivors in the United States to be 388,501, an increase of 59,849 from the previous estimate made in 2005 by the National Cancer Institute. Of these survivors, 83.5% had survived 5 or more years since their original diagnosis, and 44.9% had survived 20 or more years.
About 70% of childhood cancer survivors were estimated to have a grade 1 or 2 (mild/moderate) chronic condition, and about one-third (32%) were estimated to have a grade 3 or 4 (severe/disabling or life-threatening) chronic condition. An estimated two-thirds (68%) of childhood cancer survivors had any chronic condition 5 to 14 years after diagnosis, with this number increasing to 77% and 85% at ages 15 to 24 and 25 to 37 years after diagnosis, respectively. Estimates for specific morbidities ranged from 12% (pain) to 35% (neurocognitive dysfunction).
Generally, morbidities increased by age. However, mental health and anxiety remained fairly stable, and neurocognitive dysfunction exhibited initial decline and then remained stable by the time since diagnosis.
“Our study findings highlight that a singular focus on curing cancer yields an incomplete picture of childhood cancer survivorship,” said Siobhan M. Phillips, PhD, MPH, Assistant Professor of Preventive Medicine at Northwestern University Feinberg School of Medicine in Chicago and corresponding author of the study, in a statement. “The burden of chronic conditions in this population is profound, both in occurrence and severity. Efforts to understand how to effectively decrease the morbidity burden and incorporate effective care coordination and rehabilitation models to optimize longevity and well-being in this population should be a priority.… We need to develop a better understanding of the multilevel factors, including, but not limited to, physical activity, diet, and treatment characteristics, which influence childhood cancer survivors’ susceptibility to these morbidities in order to effectively prevent and delay their onset.”
Dr. Phillips is the corresponding author of the Cancer Epidemiology, Biomarkers & Prevention article.
Funding for this study was provided by the National Institutes of Health. The study authors reported no conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
