On September 18, 2026, The Lancet published a review by T. R. Rebbeck that starts from a blunt fact: the stage of a cancer when it is found is still the strongest factor in whether a person survives it [1]. Then comes the uncomfortable part: only 13% of cancers are detected through guideline-based screening, and between 20% and 50% first show up in an emergency department [1].

Rebbeck’s answer is a framework he calls precision prevention and early detection, or PPED [1]. It is an argument, not a trial, and I have only read its abstract, so I stick to what it says. My view is simple. Whether your cancer is caught early should not come down to luck, and matching screening to risk is a sensible way to reduce that luck. But the idea only earns its name if it cuts testing for people who do not need it as seriously as it adds testing for those who do.

Most cancers are still found the hard way

The emergency number deserves a closer look. In 2022, McPhail and colleagues analyzed 857,068 patients with eight types of cancer, including lung, colon, pancreatic and ovarian, across 14 regions in six high-income countries: Australia, Canada, Denmark, New Zealand, Norway and the UK [2]. They counted a diagnosis as an emergency presentation if it came within 30 days after an emergency hospital admission [2].

Depending on the region, 24.0% to 42.5% of these cancers were diagnosed that way [2]. For pancreatic cancer, the average was 46.1% [2]. And across every region, people diagnosed as emergencies had a substantially higher risk of dying within 12 months [2].

This was an observational study, so it cannot say the emergency route itself caused those deaths. The authors also found that older age and advanced stage were consistently linked to emergency presentation [2]. It fits a broader estimate from a 2022 review that about half of cancers are already at an advanced stage when diagnosed [3]. Much cancer is found only once it has made someone sick enough for a hospital.

That is the scenario Rebbeck’s framework is trying to make rarer.

What risk-based screening means

Today, most screening follows a simple rule: reach a certain age, get a certain test at a set interval. Rebbeck proposes asking four questions instead: who is at elevated risk, what preventive step fits them, when it should happen and how intensely, and how and where it should be delivered [1].

In everyday terms, someone with a strong family history or a known inherited risk might start screening earlier or more often. Someone at low risk might be screened less often, or not at all for some cancers. The review puts it plainly: “De-escalation of preventive interventions in low-risk individuals is as important as preventive care escalation in high-risk individuals” [1].

I think that is the most important sentence in the abstract. Precision medicine is usually sold as doing more. Here the promise includes doing less, on purpose, for people who gain little from being tested.

There is reason to believe the logic can work. Rebbeck points to hereditary cancer syndromes, where people carry a much higher inherited risk, as evidence that this approach works “when cancer risk is sufficiently enriched” [1]. That qualifier matters: working in high-risk families is not the same as working across a whole population.

This topic is close to my own training. My PhD in medical physics focused on Protein L functionalized microparticles for molecular imaging of early colorectal lesions, and today I build deep-learning models that use breast MRI to help tell inflammatory breast cancer apart from other locally advanced breast cancers. From that angle, I think seeing something earlier helps only if you can tell which findings matter.

Early is not automatically better

Screening has real wins. Colorectal and cervical cancer screening has been shown to reduce deaths from those cancers, largely because doctors can remove precancerous growths before they turn into cancer [4]. That is early detection at its best.

It also has real costs. Overdiagnosis means finding a disease that would never have caused symptoms or death during a person’s lifetime [4]. Pooling several studies, one review estimated that about 25% of breast cancers found by mammography and 50% to 60% of prostate cancers found by PSA blood tests are overdiagnosed [4]. People who are overdiagnosed can go through surgery, radiation or chemotherapy they never needed, along with the stress and anxiety that come with a cancer diagnosis [4].

A false positive is a different problem: a positive test in someone who does not have cancer at all [4].

There is a quieter trap too. Most screening tests are better at catching slow-growing tumors than fast ones [4]. Here is a simple illustration of another one: if a test finds a cancer two years earlier but the person dies on the same day they would have anyway, their survival after diagnosis looks two years longer even though nothing changed. Researchers call this lead-time bias, and it is why rising survival numbers alone do not prove a test saves lives. For breast and prostate cancer, screening brought a spike in early-stage diagnoses, but a clear link to fewer cancer deaths has been harder to show [4].

The honest case for caution

The strongest argument against risk-based screening is about fairness. A risk score is only as good as its data, and a tool built mostly on one population may misjudge risk in others. If the extra screening for high-risk people only reaches those with good insurance and a nearby clinic, the gap between groups could grow instead of shrink.

Rebbeck does not claim the hard parts are solved. He writes that the science must still mature, and that the infrastructure and workforce needed to support long-term prevention planning are a defining cancer control challenge for the next decade [1]. I read that as an admission that the framework is ahead of the systems that would run it.

The critics are right that more testing is not automatically better, and that is exactly why scaling back for low-risk people matters. Where I would push harder is on evidence. Crosby and colleagues wrote in 2022 that it is vital to understand who is at greatest risk and to identify the early disease that truly needs treatment [3]. Until we can do both, every new screening plan should be tested against the outcome that matters most: fewer people dying of cancer.

What this means for you

For readers, the basics still apply. Know your family history, keep up with the screening your doctor recommends for your age, and do not ignore symptoms that linger for weeks. When offered a new test, it is fair to ask what it can find, what happens if it is positive, and whether it has been shown to prevent deaths. A good screening program should give you clear answers to all three.

References

[1] T. R. Rebbeck, “Precision prevention and early detection: framework for a new clinical cancer control pathway,” The Lancet, published online Sep. 2026, doi: 10.1016/S0140-6736(26)01669-7.

[2] S. McPhail, R. Swann, S. A. Johnson, M. E. Barclay, H. Abd Elkader, R. Alvi, et al., “Risk factors and prognostic implications of diagnosis of cancer within 30 days after an emergency hospital admission (emergency presentation): an International Cancer Benchmarking Partnership (ICBP) population-based study,” The Lancet Oncology, vol. 23, no. 5, pp. 587-600, May 2022, doi: 10.1016/S1470-2045(22)00127-9.

[3] D. Crosby, S. Bhatia, K. M. Brindle, L. M. Coussens, C. Dive, M. Emberton, et al., “Early detection of cancer,” Science, vol. 375, no. 6586, Art. no. eaay9040, Mar. 2022, doi: 10.1126/science.aay9040.

[4] S. Srivastava, E. J. Koay, A. D. Borowsky, A. M. De Marzo, S. Ghosh, P. D. Wagner, et al., “Cancer overdiagnosis: a biological challenge and clinical dilemma,” Nature Reviews Cancer, vol. 19, no. 6, pp. 349-358, Jun. 2019, doi: 10.1038/s41568-019-0142-8.