US Early-Onset Cancer Rates Rise Due to More Detection, Not Disease

Researchers from Harvard Medical School, Brigham and Women’s Hospital, and Dell Medical School suggest that the uptick in early‑onset cancer diagnoses across the United States may be largely a result of increased detection rather than a genuine rise in the disease itself.

Over the past several decades, heightened public awareness and prevention efforts have helped eliminate many environmental cancer risks. Consequently, overall cancer mortality among adults under 50 has fallen by almost fifty percent since the mid‑1990s.

Despite this progress, the public’s worry has grown as more young adults receive diagnoses and high‑profile cases draw attention. The number of PubMed references concerning early‑onset cancer has more than tripled, and recommendation ages for screening have been lowered to 45 for colorectal cancer and 40 for breast cancer. It remains unclear whether the higher case counts reflect a true increase in cancer incidence or merely more frequent diagnoses.

In the study titled “The Rise in Early‑Onset Cancer in the US Population—More Apparent Than Real,” published in JAMA Internal Medicine, investigators examined cancer incidence and mortality trends to determine whether the rising number of diagnoses in people younger than 50 indicate clinically significant disease.

Data spanned eight cancers that have shown the fastest rise in incidence since 1992—thyroid, anal, kidney, small intestine, colorectal, endometrial, pancreas, and myeloma. Together, these cancers doubled in incidence, while overall mortality remained steady at 5.9 deaths per 100,000 from 1992 to 2022.

The team used population‑based incidence data from the Surveillance, Epidemiology, and End Results (SEER) program and mortality data from the National Vital Statistics System. They analyzed aggregate and site‑specific trends, applied three‑year moving averages, and examined metastatic disease at diagnosis.

Colorectal cancer mortality rose modestly while incidence increased more rapidly. Neuroendocrine tumors and reclassified appendiceal cancers may help explain the higher number of diagnoses. For endometrial cancer, the parallel rise in incidence and mortality correlates with rising obesity rates and fewer hysterectomies, both of which elevate risk.

Thyroid and kidney cancers demonstrated sharp increases in incidence but stable or declining mortality, a pattern consistent with overdiagnosis through imaging and lower diagnostic thresholds.

Pancreatic, small intestine, and myeloma cancers showed similar trends: rising incidence without corresponding mortality increases, supporting the idea of incidental detection and earlier diagnosis. Anal cancer incidence spiked then fell, likely reflecting shifts in HPV/HIV epidemiology, while mortality remained unchanged.

Breast cancer, although not the fastest‑rising by relative increase, accounted for one of the largest absolute surges in early‑onset diagnoses, with over 100,000 additional cases reported since 1992. Mortality from breast cancer fell by 50%, reflecting advances in systemic treatment. The excess diagnoses largely represented early‑stage disease identified via expanded screening.

Authors conclude that the apparent epidemic of early‑onset cancers appears to stem more from enhanced detection than from an actual boom in life‑threatening disease.

While some increases in clinically significant cancers exist, they are small and specific to certain sites. The authors warn that interpreting rising incidence as evidence of an epidemic could lead to unnecessary screening, overdiagnosis, and treatment, diverting attention and resources from other pressing health threats to young adults, such as the growing deaths from suicide and unintentional injuries.

Written for you by our author Justin Jackson, edited by Sadie Harley, and fact‑checked and reviewed by Robert Egan—this article is the product of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You’ll receive an ad‑free account as a thank‑you.