Appendix cancer is a condition that, until recently, was so rare that most people never gave it a second thought, for decades being something that doctors might encounter only once or twice in a career – and almost always in older adults.
But now a surprising and concerning trend is emerging: appendix cancer is being diagnosed more often, and increasingly affecting people in their 30s, 40s and even younger. This shift has left many experts puzzled and searching for answers, writes Justin Stebbing in The Conversation.
While the purpose of the appendix is still debated, it’s best known for causing appendicitis, which often requires emergency surgery. What’s less well known is that cancer can develop in the appendix, usually without any warning signs.
A recent study, published in Annals of Internal Medicine, has shown that the number of appendix cancer cases has increased dramatically among people born after the 1970s. In fact, the incidence has tripled or even quadrupled in younger generations compared with those born in the 1940s.
While the overall numbers are still small (appendix cancer affects just a handful of people per million each year) the rapid rise is striking. Even more notable is that about one in three cases now occurs in adults under 50, a much higher proportion than seen in other types of gastrointestinal cancers.
So, what's behind this surge?
No one knows for sure, but one of the first suspects is the dramatic change in lifestyle and environment over the past several decades. Obesity rates have soared since the 1970s, and being overweight is a known risk factor for many cancers, including those of the digestive system.
At the same time, diets have shifted toward more processed foods, sugary drinks and red or processed meats, all of which have been linked to increased cancer risk in other parts of the gut.
Physical activity has also declined, with more people spending long hours sitting at desks or in front of screens.
Another possibility is that we are being exposed to new environmental factors that previous generations didn’t face. The industrialisation of food production, the widespread use of plastics and chemicals, and changes in water quality might all play a role. However, the evidence is still in its early stages.
Hard to detect
What makes appendix cancer especially challenging is how difficult it is to detect. Unlike colon cancer, which can sometimes be found early through screening colonoscopies, appendix cancer usually flies under the radar.
The symptoms, if they appear at all, are vague and easy to dismiss. People might experience mild abdominal pain, bloating or changes in bowel habits, which are common complaints for many benign conditions. As a result, most cases are only discovered after surgery for suspected appendicitis, when it’s often too late for early intervention.
Despite the rise in cases, there is no routine screening test for appendix cancer. The disease is simply too rare to justify widespread screening, and the appendix can be difficult to visualise with standard imaging or endoscopy. This means that both patients and doctors need to be extra vigilant.
If a patient experiences persistent or unusual abdominal symptoms, especially if they’re under 50, it’s important not to ignore them. Early investigation and prompt treatment can make a significant difference in outcomes.
The increase in appendix cancer among younger adults is part of a broader trend seen in other gastrointestinal cancers, such as those of the colon and stomach. These cancers, too, are being diagnosed more often in people under 50, suggesting that shared risk factors may be at work.
The reasons for this shift are complex and probably involve a mix of genetics, lifestyle, environment and perhaps even changes in our gut microbiome – the bacteria in our intestines that live with us.
Over the past few decades, antibiotics have been used more frequently, both in medicine and in agriculture. This widespread use can alter the balance of bacteria in our guts, which might influence cancer risk.
Some recent research suggests that early-life exposure to antibiotics could have long-term effects on the digestive system, but more studies are needed to confirm this link.
For now, the best advice is to focus on prevention and awareness.
Justin Stebbing – Professor of Biomedical Sciences, Anglia Ruskin University, Cambridge, England
See more from MedicalBrief archives:
Appendix cancer spikes among Gen Xers, millennials – US review
Getting to the bottom of cancer rise among young people
Non-operative appendicitis treatment a better option, argue surgeons