NEW YORK, June 15: Though still extremely rare, appendix cancer is becoming more common, particularly among younger generations, according to a new study published in the Annals of Internal Medicine.

An analysis of data from the National Cancer Institute has revealed that rates of appendix cancer have tripled among Generation X and quadrupled among millennials when compared to older generations.

“There is a disproportionate burden of appendix cancer among young individuals,” said Dr. Andreana Holowatyj, the study’s lead author and assistant professor of hematology and oncology at Vanderbilt University Medical Center and Vanderbilt Ingram Cancer Center.

Holowatyj noted that earlier research had already shown that one in three appendix cancer cases occurs in adults under 50, a significant contrast to colorectal cancer, where only one in eight cases affects those under 50.

Appendix cancer remains extremely rare, with the National Cancer Institute estimating an annual incidence of only 1 to 2 cases per million people in the U.S.

To examine trends over time, Holowatyj and her team analyzed data from the Surveillance, Epidemiology, and End Results (SEER) program, which covers nearly half of the U.S. population. Between 1975 and 2019, a total of 4,858 appendix cancer cases were recorded.

The generational increase in younger patients diagnosed with appendix cancer highlights the urgent need to investigate underlying causes, Holowatyj said. “It’s important that we find the causes underpinning these statistics in order to reverse this trend and reduce the disease burden.”

Experts say this pattern reflects a broader rise in gastrointestinal cancers among younger adults. Dr. Andrea Cercek, co-director of the Center for Early Onset Colorectal and GI Cancers at Memorial Sloan Kettering Cancer Center, emphasized that while the exact cause remains unclear, environmental and lifestyle factors may be playing a role.

“It’s likely that there are environmental causes, including exposures through food, water, and microplastics, as well as lifestyle and dietary changes,” Cercek said. “It’s probably not one single factor but multiple contributing elements since 1945.”

The appendix, a small pouch attached to the large intestine, is best known for causing appendicitis. Unlike other gastrointestinal cancers, appendix cancers are harder to detect on scans or through colonoscopy. Dr. Deborah Doroshow of the Icahn School of Medicine at Mount Sinai noted that most appendix cancers are not identified until after a patient undergoes surgery for appendicitis.

“About 95% of appendix cancers are discovered only after removal and pathological examination of the appendix,” Holowatyj added. This typically results in later-stage diagnoses and poorer outcomes.

Doroshow, who was not involved in the study, stressed the importance of paying attention to subtle symptoms, especially among younger people. Persistent fatigue, unexplained pain, or weight loss should not be overlooked.

“If a person feels something is wrong, it’s always best to seek a medical opinion,” Doroshow said. “We’ve seen young patients with cancer who were initially dismissed because of their age.”

She also urged women and people of color to advocate for themselves, as their concerns are more likely to be underestimated.

Still, Doroshow cautioned against overreacting to occasional discomfort. “Not every abdominal pain is a cause for concern,” she said. “It’s the persistent or unusual symptoms that should prompt evaluation.”