Disparities Remain in Pediatric Cancer Despite OS Improvement Over 14 Years

Pediatric cancer mortality and survival has only improved over the past 40 years in the United States (US). However, there are often various factors that play a role including age, race/ethnicity, cancer site, and economic status, which can change the outcome or treatments of individuals.

Because of this, a study was developed to assess recent mortality and survival data for individuals younger than 20 years of age. Surveillance data for pediatric cancer since 2001 was thoroughly examined as well as recent trends.

Data from the National Vital Statistics System ranging from 2002-2016 were used in the study to calculate age-adjusted death rates. Annual percent changes (APCs) and average annual percent changes (AAPCs) were calculated with joinpoint regression.

Five-year relative survival was calculated on the basis of National Program of Cancer Registries data for 2001-2015. Death rates and survival were estimated overall and by sex, 5-year age group, race/ethnicity, cancer type, and county-based economic markers.

It was reported that death rates decreased during 2002-2016 (AAPC, –1.5), steeper declines occurred between 2002-2009 (APC, –2.6), and that the study ended with a plateau (APC, –0.4).

The most common causes of deaths from pediatric cancer were linked to leukemia and brain cancer, but brain cancer surpassed leukemia in 2011. While findings showed leukemia and lymphoma to have a decrease in death rates, results remained unchanged for brain, bone, and soft-tissue cancers.

Additionally, survival improved from 82.0% to 85.1% from 2001-2007 to 2008-2015. Females aged 15-19, non-Hispanic Whites and those who were in counties in the top 25% by economic status had the highest rate of survival within both periods. Survival improved for leukemias, lymphomas, and brain cancers but mostly stayed the same for bone and soft-tissue cancers.

The findings were positive as it reported overall death rates to have decreased and survival to have increased. Differences still are prominent and exist in sex, age, race/ethnicity, cancer type, and economic status. Because of this, improving therapies, access to care, and supportive and long-term care will all be important next steps for the improvement of pediatric care outcomes.

In an interview with Targeted Oncology^TM, David Siegel, MD, MPH, pediatric hematologist/oncologist, and a lieutenant commander in the Commissioned Corps of the US, explained the many changes seen in pediatric cancer mortality and survival over the past 40 years.

Can you pinpoint any therapeutic advancements that may have contributed to the improvement in pediatric cancer survival?

We have seen many changes over the last 40 years, great improvements in both survival and in mortality, mortality being death rates, and our paper looked at improvements in both survival and mortality over the last 20 years.

There's been a number of different improvements in specific therapies. There have also been improvements in how supportive care is provided and how existing therapies are better utilized to meet patient needs.

Can you discuss the methods used to carry out the research published in Cancer?

This study used 2 different systems. One was called the National Vital Statistics System, and that looked at mortality data from 2002-2016. We also used the national program of cancer registries, which uses cancer registries to provide survival statistics from 2001-2015. For that system, we could cover 93% of the US population, and the first database could cover 100% of the US population.

We were able to complete the study through the use of national cancer registries. It's really nice to have that as a tool, and national surveillance is really important for understanding how to best target therapies and research in the future.

What were the key findings of the study?

The key findings were that we saw that mortality improved over the last 20 years. We did see that mortality was improving specifically for leukemia, lymphoma, and certain endocrine cancers, but improvements were not seen in bone cancer, brain cancer, and some soft tissue cancers.

To improve survival in bone cancer and tough tissue cancers, better advances in novel therapeutics and new therapies will be really important. It will also be helpful to find any way we can to improve supportive care, and also better utilize the therapies we currently have. There have been some nice improvements in immunologic therapies, specifically, CAR T-cell therapies, which may have improved mortality in those groups.

What findings related to disparities stood out in the study?

We did find improvements in mortality for several different race and ethnicity groups. That consisted of non-Hispanic White children and adolescents, non-Hispanic Black children and adolescents, and Hispanic children and adolescents. It was great to see mortality improving for all those three groups.

We did see disparities in the survival statistics, though. We saw that non-Hispanic Black children and adolescents had lower survival of non-Hispanic White children and adolescents. We also saw higher death rates in counties of lower education levels and in counties with higher poverty.

REFERENCE:

Siegel DA, Richardson LC, Henley SJ, et al. Pediatric cancer mortality and survival in the United States, 2001-2016. Cancer. 2020;126(19):4379-4389. doi:10.1002/cncr.33080