According to Korea's 2023 national cancer registration statistics, published by the Ministry of Health and Welfare in January 2026, the probability of developing cancer over an average lifespan is 44.6% for men and 38.2% for women — one in two men, one in three women. 288,613 people were newly diagnosed in 2023, and 2,732,906 people were living with or after cancer: one Korean in nineteen.
The same statistics carry a second number. Among patients diagnosed in the most recent five years, the five-year relative survival rate is 73.7%, up 19.5 percentage points from 54.2% for those diagnosed in 2001–2005. Seven in ten survive five years or more. What sits between those two numbers is early detection, and Korea's institutional mechanism for it is the national cancer screening programme. The general national health check-up that arrives alongside it runs on its own rules for who is due and when.
1. When does what start for me. Korea's national screening adds one item each time you reach an age — cervical at 20, then stomach, breast and liver all at once at 40, then 50. That is where most people miss one.
2. Why bother. Lifetime probability of developing cancer is 44.6% for men and 38.2% for women. Yet the five-year relative survival rate is 73.7%, up 19.5 percentage points from 54.2% in 2001–2005 — what sits between those two numbers is early detection.
3. What does it cost. Costs, what “high-risk group” precisely means, and what changes from 2028 are all below.
This guide is organised not as a list of six cancers but around a single question: what starts at my age?
What starts at my age
The programme adds an item each time you reach a threshold age. In particular, three start at once in the year you turn 40. That is where most people fall through.
| Age | What begins that year | Interval | Who |
|---|---|---|---|
| 20 | Cervical cancer | 2 years | Women |
| 40 | Stomach cancer | 2 years | All |
| Breast cancer | 2 years | Women | |
| Liver cancer | 6 months | High-risk group | |
| 50 | Colorectal cancer | 1 year | All |
| 54 | Lung cancer | 2 years | 30+ pack-year smokers |
| 74 | Lung cancer eligibility ends | — | — |
The column to watch is interval. Most are two years, but liver cancer is six months and colorectal is one year. Those two cannot be filed under the same rhythm as the rest. The high-risk liver group in particular needs two screenings a year; settling into a two-year habit means skipping half of them.
The six cancers — when and how
The same information arranged by cancer type. The method column matters: knowing what the test actually is prevents confusion when booking.
| Cancer | Eligibility | Interval | Method |
|---|---|---|---|
| Stomach | 40 and over, all | 2 years | Upper endoscopy (or upper GI series) |
| Colorectal | 50 and over, all | 1 year | Faecal occult blood test → colonoscopy if abnormal |
| Liver | 40 and over, high-risk | 6 months | Liver ultrasound + serum AFP |
| Breast | Women 40 and over | 2 years | Mammography |
| Cervical | Women 20 and over | 2 years | Cervical cytology |
| Lung | 54–74, high-risk | 2 years | Low-dose chest CT |
The colorectal row is the unusual one. The programme's first-line test is not a colonoscopy but a faecal occult blood test — a sample collected at home and submitted. A colonoscopy follows only if blood is detected. Arriving expecting a state-funded colonoscopy is a common mismatch.
What does “high-risk group” precisely mean
This condition, attached only to liver and lung cancer, is not a judgement call. It has an administratively fixed definition, quoted here from the National Cancer Information Center.
| Group | Definition |
|---|---|
| Liver, high-risk | Aged 40+ who, in the two years preceding the screening year, received medical care under the relevant diagnostic codes for liver cirrhosis, hepatitis B surface antigen positivity, hepatitis C antibody positivity, or chronic liver disease caused by hepatitis B or C |
| Lung, high-risk | Aged 54–74 with a smoking history of 30 pack-years or more, confirmed either by the general health screening questionnaire within the preceding two years, or by the questionnaire completed when joining the national health insurance smoking-cessation programme |
What both definitions share is that eligibility is established by medical records or a questionnaire — meaning it is determined automatically, not by applying. A hepatitis B carrier who has not received care under those codes in two years may drop out of the list, and a smoker who never completed a general screening questionnaire will not be flagged for lung screening.
Thirty pack-years means packs per day multiplied by years smoked: a pack a day for 30 years, or two packs a day for 15. The Fifth Comprehensive Cancer Control Plan adds that former smokers who quit more than 15 years ago are excluded.
What does it cost
Mostly nothing, or 10%. The National Cancer Information Center's stated basis:
| Category | Your share | Exception |
|---|---|---|
| Insured, upper 50% by premium | 10% of the fee | Colorectal and cervical are free |
| Insured, lower 50% by premium | Free | — |
| Medical aid recipients | Free | — |
The “upper 50%” line is drawn by premium. For 2024 eligibility, the lower half meant a monthly premium of ₩125,000 or less for employee subscribers and ₩67,500 or less for regional subscribers (assessed as of November 2023). Above that line you pay 10% — ₩10,000 on a ₩100,000 test.
One thing that regularly catches people out: only the first-line test follows this cost basis. If the faecal test comes back abnormal and you move to a colonoscopy, or a biopsy is taken during an endoscopy, that becomes ordinary insured treatment with its own co-payment. Reading the numbers on a screening result sheet is covered in how to read your health check results.
How many people actually go
From the National Cancer Center's screening behaviour survey, released in March 2025. Guideline-compliant participation stood at 70.2% in 2024, up 31.4 percentage points from 38.8% in 2004 and 3.8 points on the previous year.
| Cancer | 2024 guideline-compliant participation |
|---|---|
| Stomach | 77.4% |
| Colorectal | 74.4% |
| Breast | 70.6% |
| Cervical | 62.0% |
| Overall | 70.2% |
The lowest is cervical cancer at 62.0% — eligible from age 20 and free regardless of income, yet more than one in three eligible people does not attend. The earliest starting age appears, if anything, to produce a sense that it is not yet relevant.
Liver and lung are absent from this table because the release published figures for only four cancers. Another document (the Fifth Comprehensive Cancer Control Plan) contains participation rates for all six, but on a different calculation basis that cannot be placed in the same table, so they are left out rather than mixed in.
What comes before screening
Early detection finds a cancer that already exists. The step before it is the National Cancer Prevention Guidelines from the National Cancer Center and the Ministry of Health and Welfare, quoted here in full.
- Do not smoke, and avoid other people's tobacco smoke
- Eat plenty of vegetables and fruit, and keep the diet varied and balanced
- Do not eat salty food, and avoid charred food
- For cancer prevention, avoid even one or two drinks a day
- Walk or exercise enough to sweat, at least 30 minutes a day, five or more days a week
- Maintain a healthy weight for your build
- Receive hepatitis B and cervical cancer vaccinations per the immunisation guidelines
- Practise safe sex to avoid sexually transmitted infections
- Follow workplace safety and health rules to avoid exposure to carcinogens
- Attend cancer screening without gaps, per the early detection guidelines
Rule 4 departs from the common view. It is not “drink in moderation” but “avoid even one or two drinks a day” — that is, no safe drinking level is set from a cancer prevention standpoint.
Rule 7 is also worth pausing on: there are two cancers where vaccination is prevention. Hepatitis B vaccine connects to liver cancer, HPV vaccine to cervical cancer — the same two that get special treatment in the screening table, at a six-month interval and a start age of 20.
Rule 10 returns to the tables above; the last item on a prevention list is screening. How to read the numbers on a screening result sheet is in reading your health check results, and the item screening flags earliest — fasting glucose — continues in signs of prediabetes.
What changes from 2028
The Fifth Comprehensive Cancer Control Plan (2026–2030), published by the Ministry of Health and Welfare in February 2026, sets out two changes to screening, each with a stated start year.
- Colorectal — colonoscopy introduced (from 2028), based on the 2019–2024 colonoscopy pilot and the November 2025 guideline revision. The current faecal occult blood system changes.
- Lung — eligibility expanded (from 2028), based on overseas practice and guideline revision. Korea's new thresholds are not specified in the document; it only notes the US precedent of lowering 55 to 50 and 30 pack-years to 20.
In short, the tables above hold through 2027. If you are approaching an eligibility age now, plan on the current basis.
One thing to handle this year
One item per stage of life.
- Women in their 20s and 30s — your cervical screening history. Eligible from 20, free for everyone, and the lowest participation of all at 62.0%. If you have never attended, this is the year.
- The year you turn 40 — stomach and breast begin together. Also check whether you carry hepatitis B or C: if so, liver screening starts alongside them on a six-month cycle.
- The year you turn 50 — colorectal is annual. Its rhythm differs from the two-year items, so mark it separately from the first year.
- Smokers aged 54+ — work out your pack-years (packs per day × years). If you are over 30 and have had no screening notice, the cause may be that your smoking history was never recorded on a general health screening questionnaire.
- Everyone — prevention rule 4. Cutting alcohol is the most immediately actionable of the ten.
Eligibility and this year's notices can be checked on the National Health Insurance Service website or its app, and screening must be booked as national cancer screening at a designated provider to be covered. What “a healthy weight” in prevention rule 6 means for your own build can be checked in the BMI calculator, and regular testing for post-menopausal women is in osteoporosis prevention and testing.
Questions that remain
What starts when I turn 40?
Three things start in the same year — stomach, breast and liver cancer screening. The national programme adds one item at a time as you reach each age, and 40 is the only age where three begin at once. That is where most people lose track. Stomach screening is every two years for both sexes, breast every two years for women, and liver every six months for the high-risk group.
Why is liver cancer screened every six months?
Intervals differ by cancer, and over ten years the gap widens fourfold. The two-year items — stomach, breast, cervical and lung — come to five rounds in a decade, while high-risk liver screening is twenty and colorectal is ten. The trap is that most items are on a two-year rhythm, and settling into it means skipping half of the liver rounds. Colorectal is annual rather than biennial too, so it is worth marking separately in the first year.
Does national screening give me a colonoscopy?
Not at present. The first-line test is a faecal occult blood test — you collect a sample at home and submit it, and only if blood is detected does it proceed to colonoscopy. Turning up expecting a colonoscopy is a common mismatch. That said, the Fifth Comprehensive Cancer Control Plan includes introducing colonoscopy from 2028. Through 2027 the current system stands.
Do I apply to be in a high-risk group?
No — it is determined automatically from records. For liver cancer the basis is medical care received under cirrhosis or hepatitis B/C diagnostic codes in the two years before the screening year; for lung cancer it is smoking history recorded on the general health screening questionnaire or the smoking-cessation programme questionnaire. So a hepatitis B carrier who has not been treated under those codes for two years can drop off the list, and a smoker who never filled in the questionnaire will not be flagged. Thirty pack-years is packs per day times years smoked, and former smokers who quit more than 15 years ago are excluded.
What does the screening cost?
Free for the lower half by health insurance contribution and for medical aid recipients; the upper half pays 10% of the cost. Even in the upper half, colorectal and cervical screening are free. One thing catches people out: that cost structure covers the first-line test only. Once an abnormal faecal occult blood result leads to a colonoscopy, or a biopsy is taken during a gastroscopy, it becomes regular insured medical care with its own co-payment.
Where to check further
- Whether you are eligible this year. Some items alternate by odd or even birth year, so you are not eligible every year — the National Health Insurance Service (1577-1000) and its app show your eligibility and the window remaining.
- Whether you fall into the liver cancer high-risk group. This article goes as far as the definition — the actual determination uses the Service's own medical records, so check the notice you receive or ask directly.
- What happens after an abnormal result. Outside this article — the National Cancer Information Center (1577-8899) covers diagnosis and treatment pathways by cancer type, along with medical cost support schemes.
Sources and where to verify
- National Cancer Information Center — eligibility and notification (ages and intervals for the six cancers; liver and lung high-risk definitions)
- National Cancer Information Center — screening costs (10% for the upper half; colorectal and cervical free; lower half and medical aid free; premium thresholds)
- National Cancer Information Center — the ten national cancer prevention rules
- Ministry of Health and Welfare — 2023 national cancer registration statistics (20 Jan 2026 · 288,613 new cases; 2,732,906 prevalent; 44.6% / 38.2% lifetime probability; 73.7% five-year survival)
- Ministry of Health and Welfare — Fifth Comprehensive Cancer Control Plan (2026–2030) (24 Feb 2026 · colonoscopy and lung expansion from 2028; 15-year quit exclusion)
- National Cancer Center — 2024 cancer screening behaviour survey (11 Mar 2025 · 70.2% overall; stomach 77.4, colorectal 74.4, breast 70.6, cervical 62.0)
- National Health Insurance Service — check your screening eligibility
Written as of July 2026. Ages, intervals and costs are transcribed from the sources above; the premium thresholds are the 2024 eligibility figures assessed as of November 2023. The widely repeated rule that “two-year items apply in even years to people born in even years and odd years to those born in odd years” is deliberately not included here. That wording could not be found for national cancer screening in any source from the National Cancer Information Center, the Ministry of Health and Welfare or the National Cancer Center; the only verified instance was the National Health Insurance Service stating it for general health screening for people aged 20–39. It may well hold in practice, but since the basis could not be confirmed, check your own eligibility directly with the Service. Participation rates for liver and lung cancer are also omitted, because two public documents give different values on different calculation bases. This article does not replace a medical diagnosis.
