Early-Onset Cancer Incidence in the US Increased Through 2010s

There was a rise in early-onset cancer incidence between 2010 and 2019, according to new research published today in JAMA Network Open.

Looking at specific cancer types, the research showed that breast cancer had the highest number of incident cases in 2019, while gastrointestinal cancers had the fastest-growing incidence rates.

The study authors utilized data from 17 National Cancer Institute Surveillance, Epidemiology, and End Results registries spanning from January 2010 to December 2019, focusing on early-onset cancers. They extracted age-adjusted incidence rates per 100,000 individuals and data analysis was conducted between October 2022 and May 2023. Data from 562,145 patients with early-onset were included, with most patients being in their 40s (57.7%), female (62.5%), and White (56%).

The number of early-onset cancer cases grew from 56,051 diagnosed in 2010 to 56,468 diagnosed in 2019, reflecting a 0.74% increase. During this time, the age-standardized incidence rate of early-onset cancer increased overall with an annual percentage change (APC) of 0.28% (95% CI, 0.09%-0.47%; P = .01) and in women with an APC of 0.67% (95% CI, 0.39%-0.94%; P = .001). However, cancer incidence rates actually decreased for men, with an APC of –0.37% (95% CI, −0.51% to −0.22%; P < .001).

On average, early-onset cancer incidence increased for American Indian or Alaska Native people by 1.97% annually, Hispanic people by 1.43% annually, and Asian or Pacific Islander people by 0.97% annually. Incidence remained about the same for White people with an APC of 0.04%, while there was a decrease of −0.47% annually for Black people.

The study also revealed variations in incidence based on age group. Patients aged 30-39 years saw a clear annual increase of 0.91%, while incidence remained relatively stable for patients aged 0-29 and 40-49.

Meanwhile, there was a general decrease among individuals aged 50 years and older, with incidence rates decreasing as age increased. The mean APC was −0.48% for patients in their 50s, −0.75% for patients in their 60s, −1.01% for patients in their 70s, and −1.16% for patients aged 80 years and older.

“Further research is required to fully elucidate the reasons for these disparities,” the authors said.

In 2019, most incident cases of early-onset cancer were in the breast, with 12,649 diagnosed cases. Through the 2010s, gastrointestinal cancers exhibited the fastest-growing incidence rates among all early-onset cancer groups, with an APC of 2.16% (95% CI, 1.66%-2.67%; P < .001).

“Because gastrointestinal cancers had the fastest-growing incidence rates among the organ systems, we further explored the incidence patterns among individual gastrointestinal cancers to identify the specific organs contributing to this pattern,” the authors noted.

In 2019, the number of incident cases was highest for cancers in the colon and/or rectum (n = 4,097), stomach (n = 773), and pancreas (n = 701).

Between 2010 and 2019, the most substantial increases in incident cases were seen in the appendix, intrahepatic bile duct, and pancreas (18.21%; from 593 to 701 cases). The number of cases in the appendix jumped by 251.89%, from 185 to 651 cases, and intrahepatic bile duct cases grew by 142.22%, from 45 to 109 cases. The pancreas also had a substantial but much lower increase of 18.21%, but had a larger number of cases, going from 593 cases in 2010 to 701 cases in 2019. These 3 organs also exhibited the most significant incidence annual rate increases at 15.61%, 8.12%, and 2.53%, respectively.

At the same time, the incidence rates of liver and esophageal cancers decreased, with APCs of –4.67% and –0.94%, respectively.

Finally, the greatest decreases in incidence rates occurred for cancers in the floor of the mouth (APC, −7.58%; 95% CI, −9.59% to −5.52%; P < .001), acute monocytic leukemia (APC, −6.51%; 95% CI, −8.86% to −4.11%; P < .001), and prostate cancer (APC, −6.12%; 95% CI, −8.16% to −4.04%; P < .001).

According to the authors, these results build on earlier US research exploring early-onset cancer patterns up to 2014 and 2015, and align with a recent Global Burden of Disease Study that indicated higher age-standardized incident rates of early-onset cancer in countries with a higher sociodemographic index, such as North America. The authors also said this study enhances these prior insights by offering detailed, up-to-date patterns until 2019 that consider organ system, sex, and racial factors.

“There is a need to inform health care professionals about the increasing incidence of early-onset cancer, and investigations for possible tumors need to be considered when clinically appropriate, even in patients younger than 50 years,” the authors said. “These data will be useful for public health specialists and health care policy makers and serve as a call to action for further research into the various environmental factors that may be associated with this concerning pattern.”

Reference

Koh B, Jun Hao Tan D, Han Ng C, et al. Patterns in cancer incidence among people younger than 50 years in the US, 2010 to 2019. JAMA Netw Open. Published online August 16, 2023. doi:10.1001/jamanetworkopen.2023.28171