Trends in childhood cancer: Incidence and survival analysis over 45 years of SEER data

Abstract

Background: The SEER Registry contains U.S. cancer statistics. To assess trends in incidence and survival and the impact of demographic factors among pediatric patients with cancer, we assessed nearly 5 decades (1975-2019) of data.

Methods: All patients below the age of 20 with histology-confirmed malignancy were studied. Kaplan-Meier survival curves were generated to evaluate survival trends across treatment periods and ICCC classes. JoinPoint analysis was conducted to identify changes in incidence and survival.

Results: The incidence of childhood cancer increased from 14.23 cases per 100,000 children in 1975-1979 to 18.89 in 2010-2019, with an average annual percent change of 0.73. This rise was more pronounced in several cancers, including leukemias, lymphomas, brain tumors, hepatic tumors, and gonadal germ cell tumors. Age-adjusted cancer mortality decreased from 4.9 to 2.3 per 100,000. Cancer-related mortality was consistently higher in boys than in girls, and in Black children than in White children. Survival significantly improved, with 5- and 10-year survival rates rising from 63.1% to 85.2% and from 58.8% to 82.7%, respectively. Leukemias showed a substantial increase in 5-year survival from 48.2% ± 1.7% to 85.1% ± 0.4% in 2010-2019. Lymphomas also showed significant improvement, with survival increasing from 72.9% ± 1.7% to 94.2% ± 0.3%. Despite these improvements, the survival of CNS tumors, bone tumors, and sarcomas remained suboptimal, with 5-year survival estimates of approximately 60%. Our joinpoint analysis confirmed our findings but revealed an interesting increase in the incidence of lymphomas limited to the years between 2005 and 2014.

Conclusion: This research elucidates advancements in survival among pediatric patients with cancer. The results offer critical perspectives on pediatric oncology, highlighting the imperative for ongoing innovation in therapeutics. Although the increase in incidence may partially stem from enhanced diagnostic capabilities and more comprehensive registration processes, the underlying causes remain unclear.

Fig 1

Trends in age-standardized incidence rates showing the trends of (A) ICCC classes and (B) the 20 most common cancers in pediatric patients.

Fig 2

(A) Trends in age-adjusted death rates are shown for all-cause mortality (blue) and cancer-related mortality (yellow). (B) The distribution of causes of death in children is stratified by study interval.

Fig 3. Kaplan-Meier survival curves for all pediatric patients with cancer, stratified by the study interval during which the diagnosis was made.

Fig 4. Kaplan-Meier 5-year survival curves for different ICCC classes, stratified by the study interval during which the diagnosis was made.

Abbreviations: CNS, central nervous system; GCT, germ cell tumor; STS, soft-tissue sarcoma.

Fig 5. Kaplan-Meier 5-year survival curves for the 20 most frequently observed diagnoses, stratified by the study interval.

Abbreviations: AML, acute myeloid leukemia; GCTs, germ cell tumors; GNB, ganglioneuroblastoma; NHL, non-Hodgkin lymphoma.

Fig 6

Proportions of (A) Seer stages, (B) sex, (C) race, and (D) age.

Fig 7

Survival trends stratified by (A) ICCC class, (B) sex, (C) race, (D) age groups, and (E) SEER stage.

Fig 8

JoinPoint plots of the incidence of (A) all pediatric cancers, (B-L) different ICCC classes of pediatric cancer, and (M-O) all pediatric cancers by race, as reported by the SEER 8 data set (1975–2019).

Fig 9

JoinPoint plots of the 5- and 10-year relative survival of (A) all children registered in SEER from 1975 to 2019, (B-C) grouped by sex or (D-O) ICCC class.