The appendix cancer registry exists because this disease is too rare for any single hospital, or any single country, to study on its own. Pooling patient information across borders is the only way to build a group large enough for researchers to find patterns, design trials, and change how appendix cancer is treated.

Last week I asked an artificial intelligence a question I had been circling for a long time. I wanted to know what would really happen to the world if we cured cancer. Not the emotional answer. The actual one. How many more years would people live, and what would it do to the planet.

The answer landed hard.

Modeling studies have estimated that eliminating cancer entirely would raise average life expectancy in high-income countries by only a few years. Roughly three, in many analyses. Demographers have been running this math since the 1970s and they keep arriving in the same neighborhood. A team at the University of Southern California made the point directly when they argued that interventions targeting the biology of aging could do more for population life expectancy than eliminating any single disease ever will.

Three years.

I thought about that for a while. If curing every cancer on earth barely moves the needle, then what am I doing spending my life on a cancer that turns up in one or two people per million, about 3,000 diagnoses a year in a country the size of the United States. I run a nonprofit for a disease most doctors will never see. I have spent the last six months building a patient registry, and almost all of that work is the kind nobody sees. HIPAA compliance. GDPR, because a lot of the people enrolling do not live in the United States. Data security. Writing an IRB protocol. Learning form architecture well enough to build the thing myself, badly at first and then properly. It cost money and a great many nights, and some of those nights left me frustrated and often times in tears. For about an hour it felt like I had been shouting into a canyon.

Then I went back and looked at why that number comes out so small.

Why curing cancer adds so little to the average

The reason has a name. Demographers call it competing risks, and it is one of the least intuitive ideas in public health. Nathan Keyfitz laid it out in 1977 in a paper asking what difference it would make if cancer were eradicated. Deaths would drop immediately, he wrote, and then deaths from other causes would rise to fill the gap, leaving a net long-term effect that was relatively small. Most cancer deaths happen in people over 65. When you save an 80 year old from cancer, you hand them back to heart disease, stroke, kidney failure, and dementia, all of which are already standing in line. You do not give that person thirty more years. Often you give them two or three, and the average absorbs that.

The number is small because it is dominated by people who were already near the end of their lives. Arithmetic, not a verdict on whether cancer matters.

And it does not describe appendix cancer at all.

Appendix cancer breaks the average

Roughly one in three appendix cancer diagnoses happens in someone under 50. For colorectal cancer the figure is closer to one in ten. In June 2025, Dr. Andreana Holowatyj and colleagues at Vanderbilt published a birth cohort analysis in the Annals of Internal Medicine covering nearly 4,900 people diagnosed with appendiceal adenocarcinoma. Compared with Americans born in the late 1940s, rates had tripled for those born between 1976 and 1984 and quadrupled for those born between 1981 and 1989.

That is not an American story. A team in Bristol examined every appendiceal tumor recorded in the English national cancer registry between 1995 and 2016, more than 7,000 patients, and found the incidence rose from 0.3 to 1.6 per 100,000. The steepest climbs by far were in people in their twenties and thirties. The lowest were in people in their seventies. Across those same two decades, appendix removal rates in England barely moved, which undercuts the comfortable explanation that surgeons are simply finding more of what was always there.

The same direction of travel shows up elsewhere. A separate analysis of Canadian and American registries found a 292 percent rise in Canada. Researchers in Australia have reported increases in both incidence and mortality there. Different countries, different registries, the same overall direction.

One thing deserves precision. Much of the English increase came from neuroendocrine tumors, and those authors are careful to say that changes in how pathologists classify such tumors account for part of it. The pattern shows up in country after country. The full explanation is not settled in any of them.

What is not in doubt is who this disease is landing on. Those patients do not have a queue of other diseases waiting behind them. A 38 year old sitting in a surgeon’s office with an appendiceal tumor is not going to die of heart failure next year. She has three or four decades in front of her, and when this disease takes someone at that age, it takes all of them.

Measure impact in years of life instead of headcount and appendix cancer stops looking like a rounding error.

Rare is only rare one disease at a time

Taken alone, every rare cancer is small. Taken together, they make up somewhere between a fifth and a quarter of every cancer diagnosis, and the exact share depends on where you draw the line. The RARECARE project in Europe, counting cancers that affect fewer than six people per 100,000 each year, found about 541,000 new rare cancer diagnoses annually across the continent, or 22 percent of all cancers. The National Cancer Institute in the United States uses a wider threshold and puts the figure at 27 percent of diagnoses and 25 percent of cancer deaths. A later study comparing 18 American registries with 94 European ones found the burden runs at a broadly similar scale on both sides of the Atlantic. Whichever definition you take, roughly one in four or five people who hear the word cancer are hearing it about something rare.

Those patients also tend to do worse, and not because their tumors are inherently harder to treat. Fewer trials. No screening pathway. Guidelines borrowed from a different organ. Pathologists who may see three of these cases in an entire career. The gap was built by neglect, which is the good news, because neglect is reversible.

What an appendix cancer registry actually solves

Here is something I did not fully understand until I was deep inside it. The bottleneck in rare cancer research is rarely the science itself. Researchers increasingly have the molecular tools they need. What they do not have is patients they can find.

If a lab wants to study a specific mutation in appendiceal tumors, they need a group of people who carry it. In a disease this rare, no single hospital has enough of them, and no single country does either. Assembling that group from scratch takes years and burns through most of a grant before a single experiment runs, which is how so many rare cancer projects die on paper before anyone gets funded.

An appendix cancer registry removes that step. When a researcher can look at a pooled, consented, IRB-reviewed group of patients across many countries and see who carries which mutation, which subtype, which pathology finding, the most expensive part of the work is already finished. The project becomes fundable. The trial becomes designable. I built the Patient-Led Global Appendix Cancer Registry for exactly that reason, and it focuses on molecular and pathology detail rather than surveys.

Why the same diagnosis gets three different names

Pull the pathology reports for three people with the exact same appendix tumor and you will very likely get three documents that do not look like they are describing the same thing.

One says low-grade appendiceal mucinous neoplasm. One says mucinous cystadenoma with low-grade dysplasia, an older term some labs never stopped using. One says disseminated peritoneal adenomucinosis, a name that comes from a classification system most centers have moved past. Same tumor, three vocabularies, before you even get to the differences between how an American lab, an English lab, and an Australian lab lay out a report, or the fact that one pathologist writes a tidy checklist while another writes four dense paragraphs.

Think about a shelf of recipe cards. Every card is for chocolate chip cookies. One says butter, one says unsalted butter, one says two sticks. If you tried to count how many recipes use butter by matching the exact words, you would get the wrong answer every time. Somebody has to actually read each card and understand what it means before anything can be compared. Doing that by hand, one report at a time, is slow and expensive work, and it is a large part of why so much rare cancer data sits in folders doing nothing.

Artificial intelligence is useful here, and the job is far less dramatic than the headlines suggest. Within the registry, AI is not diagnosing anyone and it is not choosing treatment. It reads the report, identifies that all three of those phrases point to the same tumor, and drops the facts into the same labeled boxes every time. Diagnosis. Grade. Whether mucin was found outside the appendix. Whether the margins were clear.

Once information sits in boxes instead of paragraphs, it can be counted, and it can be counted across countries. A researcher can ask how many patients with a particular mutation also had mucin outside the appendix and get an answer in an afternoon instead of a year. For most of this disease, that question is unanswerable today.

A person still checks the work. Every record gets human review before it counts, because a machine that quietly misfiles a grade is worse than no machine at all. The AI does the reading. People do the deciding.

The cheapest way to save a life here has nothing to do with a cure

Most of the people I talk to are not struggling because the cure has not been invented yet. They are struggling because their tumor was treated like colon cancer. Because a watch and wait plan was applied that nobody had validated for their subtype. Because an antibiotic-first approach to appendicitis meant the appendix was never removed and never sent to pathology, allowing an underlying tumor to go undetected. The Bristol team raised that concern directly, writing that careful thought should be given to whether treating appendicitis with antibiotics alone is safe as a definitive strategy in younger patients.

Changing how this disease is understood and treated helps every single person diagnosed after that change lands, in every country that adopts it. It does not require a new drug. It requires evidence, evidence requires data, and data requires patients who raise their hand. You can read more about how appendix cancer treatment actually works and why specialist care matters so much.

Why I am asking you to join the appendix cancer registry this month

August is Appendix Cancer Awareness Month. Every August we share the amber ribbon and post the symptoms, and that work matters. But awareness that stops at a ribbon does not hand a researcher anything they can use.

Registering takes about fifteen minutes. You do not need your pathology report memorized. You do not need to be newly diagnosed. You do not need to live in the United States, and there is a separate form so that you do not have to. The community I work with every day spans 52 countries. This disease does not respect borders, the research should not either, and a patient in Manchester or Melbourne or Manila carries exactly the same information a researcher needs as a patient in Ohio. Long-term survivors are some of the most valuable people in the whole dataset, because the answer to why they did well is sitting in their records.

I am not going to tell you that appendix cancer will change global life expectancy. It will not. Almost nothing does, and any disease measured against that yardstick comes up short. What I will tell you is that the people who get this at 34 and 41 and 52 deserve the same shot at evidence-based care that everyone else already takes for granted. That goal is small enough to actually reach, and it starts with the registry.

Common questions

What is the Appendix Cancer Registry?

It is a patient-led global database where people with appendiceal cancers contribute their diagnostic, pathology, and molecular information so researchers can study the disease across a group large enough to draw conclusions from. It is run by Appendicure and operates under an IRB-reviewed exempt determination.

I live outside the United States. Can I still join?

Yes. There is a separate international form, linked above, built for exactly that. Records from outside the United States are not a courtesy addition to the dataset. They are essential, because differences in how appendix cancer is diagnosed and treated between countries are themselves worth studying.

Who can join?

Anyone diagnosed with an appendiceal cancer, including low-grade and high-grade mucinous neoplasms, appendiceal adenocarcinoma, goblet cell adenocarcinoma, signet ring cell carcinoma, and appendiceal neuroendocrine tumors. Caregivers can complete it on behalf of a patient.

Do I need my medical records in front of me?

No. Fill in what you know. You can come back later with pathology or genomic details. Partial information is still useful, and an incomplete entry is far better than no entry.

How is artificial intelligence used with my information?

Within the registry it is used to read documents, not to make decisions about anyone’s care. Pathology reports describe the same tumor in very different words depending on the hospital and the country, so AI sorts those words into consistent categories that can be counted. A person reviews the result before it becomes part of the dataset.

Does joining commit me to a clinical trial?

No. The registry is separate from trial enrollment. It can help you learn about trials you might qualify for, but joining creates no obligation of any kind. If you want to look at open studies right now, the Appendicure Trial Finder pulls live listings.

I was diagnosed years ago. Is my information still useful?

Yes, and possibly more useful than a recent diagnosis. Long-term outcomes are the hardest data to collect in a rare disease, because most studies lose track of patients. If you are years out, your record answers questions nobody else can answer.

Appendicure is a patient-led 501(c)(3). Every dollar goes into research, education, and the registry that makes both possible. Support the mission here.