Cancer is becoming more survivable, thanks to earlier detection and better treatments. But beneath these comforting top-line trends lie some worrying pockets of resistance. Incidence among younger adults is one such area.
Loosely defined as those under 50, cancer rates have been rising in this section of the population for at least three decades1. Cancer remains more prevalent among the elderly, but rising cases among those responsible for generating the majority of a nation’s wealth deserves attention and, Tema would argue, intervention.
The so-called “Western diet” – rich in red meats and salt and low in fiber – is thought to be a big driver of these rising rates. Research points to its impact: between 2010 and 2019, gastrointestinal cancers had the fastest-growing incidence rates among all early-onset cancers (breast cancer had the highest number of individual cases).2
Annual percentage change in early-onset cancers from 2010 to 2019 by age group
In the late-1990s, colorectal cancer was the fourth-leading cause of cancer death in both men and women younger than 50. In 2024, it was first in men and second in women.3
It is widely accepted that earlier detection has played a major role in improving cancer survival rates among the elderly. There are no scientific reasons why screening cannot play the same role among younger populations.
Colorectal cancer is frequently diagnosed late, which helps explain its high mortality rate among younger adults and the elderly. And while colonoscopy remains the gold standard for diagnosis, the procedure’s inconvenience and patients’ unwillingness to undergo a sometimes uncomfortable and embarrassing procedure blunt its effectiveness. To a lesser extent the same issues impact adherence to stool tests, which are widely used for first-line detection by screening programs.
A potential solution already exists in the form of blood-based cancer screening, but the developers in this market have, to date, struggled to gain reimbursement. Payers have limited the use of these liquid biopsies because they have failed to match the accuracy of colonoscopy and stool-based tests.
Enter Guardant, whose Shield blood test was recently the first to be approved by the FDA as a primary screening option for colorectal cancer, alongside other non-invasive methods like stool tests. It is also the first blood test that meets the requirements for Medicare coverage for detecting colorectal cancer4.
For now, Shield is only approved for those 45 years and older. But accelerating cases of colorectal cancer among the young show that there is potential rationale for earlier screening.
We’re not quite there yet. Liquid biopsies like Shield need to become more sensitive to justify the cost of screening lower risk populations at scale. Further clinical trials will be required. But technological advances could, in the future, open this market for cancer diagnostic companies.
The convenience advantage that blood-based cancer tests offer to younger people, busy with careers and caring for children and elderly patients, should also not be overlooked. They offer policy makers an opportunity to help meet a major goal: improving adherence to screening programmes. Improving detection rates and treating cancer earlier brings so many benefits to both the individual and society.
Tema believes that efforts in liquid biopsy, while still nascent, could in the long-term lead to diagnostic profiles that would address concerns about the costs and utility in larger patient populations. Guardant’s recent and first approved blood test, while not perfect, but is a step in the right direction.