Field cancerisation
Years before a tumour, whole patches of normal-looking tissue are already colonised by mutant clones (a smoker's airway, sun-exposed skin, Barrett's oesophagus). The cancer is the one clone that got further; the field explains second cancers and local recurrence.
Diagram
Pick a product above a diagram to see the nodes it hits and the escape routes below the block. Hover or tap any node or arrow for what it is; every node opens its target, glossary entry or the pathway page. Violet boxes are druggable targets.
A lawn where many patches have already turned to weeds. Any single tumour is one patch that took over; mowing it leaves the rest of the lawn ready to sprout again.
What happens
In plain words, then the glossary entries the stage rests on. Chapter 2, How a cell becomes cancer: Cancer is evolution inside a body.
Years before a tumour, whole patches of normal-looking tissue are already colonised by mutant clones (a smoker's airway, sun-exposed skin, Barrett's oesophagus). The cancer is the one clone that got further; the field explains second cancers and local recurrence.
Field cancerisation. Cancer often arises from a whole region of tissue that already carries mutations, not from one rogue cell. Sun-exposed skin, smokers' airways, and Barrett's oesophagus are patchworks of mutant clones competing long before a tumour appears.
The molecular players
The proteins and genes at this stage, with their role and how many products act on each. Listed players come from the atlas; drawn players sit as nodes in the diagrams above.
TP53 is the 'guardian of the genome', broken in half of all cancers. Fixing it directly has so far defeated every attempt, so drugs exploit what its loss makes cancers depend on.
Where medicines act
Products grouped by the node they hit, most advanced first, with the cancers an approved product is linked to. Pick one above the diagram to see it light up.
- SelinexorApprovedEndometrial cancerMultiple myelomaDiffuse large B-cell lymphoma
- OSE2101Phase 3
- KRT-232Phase 2
- EprenetapoptNegative
How tumours escape
Records tied to this stage that describe resistance, evasion or tolerance. The resistance atlas lists the routes class by class.
- being tested at scalepolicyMRI-first prostate screening with genetic pre-selection
PSA screening finds harmless prostate cancers that would never cause trouble. Selecting men by PSA plus a polygenic risk score, then MRI before any biopsy and targeted biopsy only for PI-RADS 4 to 5 lesions, finds the dangerous cancers and skips the rest; GOTEBORG-2 showed MRI-targeted biopsy halves overdiagnosis.
- early clinicalclinicAntibiotic-resistance testing from a stool sample before treating H. pylori
H. pylori eradication often fails because of antibiotic resistance. A stool DNA test showing which antibiotics will work would raise cure rates and protect antibiotics.
- speculativedataBank yearly blood from cancer survivors so future tests can be validated
To prove a leftover-cancer test works you need blood taken years before relapse. Collecting and freezing yearly samples now makes every future test testable.
- speculativeresearchDetect tumours changing cell type from RNA in the blood
Some cancers escape treatment by changing into a different kind of cell that the drug no longer affects. Tumour RNA in blood could show this shift months before a biopsy would.
- speculativeresearchOne master trial for cancer prevention drugs across many precancers
Prevention drug trials run separately in each precancer and are slow. One master protocol with shared infrastructure across Barrett's oesophagus, oral leukoplakia, lung nodules and pancreatic cysts, using regression as an intermediate endpoint and adding or dropping arms adaptively, would test several drugs at once.
- 2021observationalVaccine efficacy against persistent HPV 16/18 infection at 10 years after one, two and three doses of quadrivalent HPV vaccine in girls in IndiaLancet Oncologychanged practice
- 2014observationalJaiswal: clonal haematopoiesis, the pre-leukaemic clones in most people over 70New England Journal of Medicine
Open questions
What is not known at this stage: the atlas's own questions, the bottlenecks it bears on, and the ideas in the corpus that try to answer them.
- Which mutant clones in normal tissue matter, given that healthy skin and oesophagus are full of them?
- Can a field be treated (chemoprevention, vaccines) without harming the organ?
- being tested at scalepolicyA legislated, publicly reported 28-day standard from urgent referral to diagnosis
Set a legal limit: anyone referred with suspected cancer should be told within 28 days whether they have it. Publish how every hospital performs each month.
- being tested at scaleclinicA swallowable sponge test for reflux patients, offered in pharmacies
A pill on a string collects cells from the food pipe and finds Barrett's oesophagus, a precursor of cancer. Offering it in pharmacies to people on long-term heartburn drugs would find it early.
- being tested at scalepolicyBan commercial sunbeds
Sunbeds cause melanoma, especially when used young. Australia and Brazil have banned them. Other countries should follow and measure the effect.
- being tested at scalepolicyBlood EBV DNA screening for nasopharyngeal cancer across southern China and Southeast Asia
Nasopharyngeal cancer is common in southern China and is caused by a virus. A blood test for viral DNA finds it early, and a large study showed better survival. Scale it up.
- being tested at scalepolicyCancer warnings on alcohol labels, evaluated as a natural experiment
Most people do not know alcohol causes seven cancers. Ireland is putting cancer warnings on bottles; other countries should follow and measure the effect on drinking.
- being tested at scalepolicyCommunity-tailored HPV vaccine confidence campaigns with school-based delivery
The HPV vaccine prevents most cervical cancer, but false safety claims have cut uptake in several countries. Rebuild confidence locally and deliver the vaccine in schools.
- being tested at scalepolicyCure hepatitis C in prisons and drug services, and enrol the cured in liver cancer surveillance
Hepatitis C is now curable in weeks. Testing and treating where it is concentrated, and keeping those with scarring in surveillance afterwards, would cut liver cancer.
- being tested at scalepolicyEliminate infection-caused cancers: HPV, hepatitis B and C, H. pylori and EBV
About one in eight cancers is caused by an infection we can vaccinate against, cure or eradicate. A concerted global programme could make those cancers rare within a generation.
- being tested at scalepolicyEvaluate alcohol minimum unit pricing against cancer incidence
Scotland and Wales put a floor under the price of alcohol. Deaths from liver disease have already fallen. Cancer takes longer to show, so someone has to keep measuring for a decade.
- being tested at scaleclinicEvery lung screening visit includes stop-smoking medicine, opt-out
Lung screening is a teachable moment. Giving cessation medicine and support by default at every scan, unless the person opts out, roughly doubles quit rates.
97 more ideas are linked to this stage's pathways, targets and terms; see the rankings →
Key evidence
Papers in the corpus tied to this stage's pathways, targets and terms, newest first.
- 2026rctPerformance of a multi-cancer early detection test in the randomized controlled NHS-Galleri trialNature Medicine
- 2025rctCHALLENGE: a structured exercise programme after chemotherapy improves survival in colon cancerNew England Journal of Medicinechanged practice
- 2023rctMASAI: AI-supported mammography screening finds more cancers with half the radiologist workloadLancet Oncology
- 2023observationalPATHFINDER: the first prospective test of a multi-cancer blood test in people without symptomsThe Lancet
- 2022reviewEarly detection of cancerScience
- 2022methodsNHS-Galleri: design of the largest randomised trial of a multi-cancer blood testCancers
- 2022rctNordICC: inviting people to a screening colonoscopy reduced bowel cancer, but less than expectedNew England Journal of Medicine
- 2021observationalAlcohol caused an estimated 741,000 cancers worldwide in 2020Lancet Oncology
- 2021observationalEngland's HPV programme: cervical cancer down 87% in the first cohort vaccinated at 12-13The Lancetchanged practice
- 2021rctOvarian cancer population screening and mortality after long-term follow-up in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trialThe Lancet
- 2021observationalVaccine efficacy against persistent HPV 16/18 infection at 10 years after one, two and three doses of quadrivalent HPV vaccine in girls in IndiaLancet Oncologychanged practice
- 2020observationalCancer Statistics, 2020: Report from National Cancer Registry Programme, IndiaJCO Global Oncology
src/data/mechanics-atlas.ts). Players, medicines, escape routes, tests, ideas and papers are resolved from the knowledge graph at build time through the stage's pathways, targets and terms, so every item here has its own page and sources. Where a section is missing, the corpus has no record tied to the stage yet. Nothing here is medical advice; see about and methodology. Stage 2.5 of 56.