Breast cancer screening is the routine use of imaging — usually mammography — to look for early breast cancer in women who have no symptoms, with the aim of finding cancer before a lump can be felt and when treatment outcomes are best. In the UK, screening is offered through the NHS Breast Screening Programme to women from age 50 up to the 71st birthday, and through private screening services to a wider age range and on a more flexible schedule.
Screening is for people without symptoms. Diagnostic assessment is for people who have a symptom (a lump, a change in the breast, a discharge). The test used (mammogram, ultrasound, or MRI) and the right age to start depend on personal risk: average-risk women are screened from 50 on the NHS programme; women with significant family history or a known gene mutation are screened earlier and more intensively. If you have a symptom, do not wait for screening — see breast lump for what to do.
Orientation Why you might be reading about this
You may be wondering when to start having mammograms, whether to pay privately for a screening mammogram before your NHS invitation arrives, or whether your family history changes when screening should begin. This page explains what screening covers, what it doesn’t cover, and how the NHS programme and private screening sit alongside each other. It is not a replacement for a personalised risk assessment.
Related terms: Mammogram · Breast MRI · Breast ultrasound · Tomosynthesis · Family history · Risk assessment
Aim What screening tries to do
Breast cancer screening looks for cancer at a stage when it is small, has not spread, and is most easily treated6. It does this by imaging the breast at intervals over many years, so that any new abnormality stands out from a baseline of “normal for this person.” When screening works, it finds cancers that would otherwise have grown and presented as a lump months or years later, and the treatment is usually less extensive.
Screening does not prevent cancer — it finds cancer earlier than it would otherwise be found. The trade-off is that some screening findings turn out, after biopsy, not to be cancer (false positives), and a small fraction of cancers detected by screening would never have caused a problem in the patient’s lifetime if left alone (overdiagnosis)2. The benefit-to-harm balance is favourable in the age group where breast cancer is common26; outside that age group it is more nuanced.
NHS programme The NHS Breast Screening Programme
The standard offer in the UK:
- From age 50 up to the 71st birthday, women are invited every 3 years for a mammogram1. The first invitation arrives sometime between the 50th and 53rd birthday1 — invitations come from the local screening unit, not the GP.
- The mammogram is done at a screening centre or a mobile unit, and reads are quality-controlled by two independent radiologists.
- Women aged 71 and over are not automatically invited but can self-refer to continue screening.
- Women aged 47 to 49 and 71 to 73 may be invited in areas participating in the AgeX randomised trial — a research study (not routine programme expansion); results are expected in the mid-2020s.
The programme is comprehensive and free. Detailed information is in the official NHS material (linked at the foot of this page).
Beyond NHS When NHS screening is not enough — earlier or more intensive
For some women, the standard “from age 50 every 3 years” screening is too late, too infrequent, or both. The NHS provides additional screening pathways for these groups:
- Strong family history — typically defined by NICE CG164 criteria3 (multiple close relatives affected, especially under 50; bilateral or ovarian cancer in the family). Women in the moderate-risk category are offered annual mammography from age 40 (continuing through the NHS programme from 50); in the high-risk category, annual breast MRI from age 30 for BRCA1/BRCA2 carriers (from age 20 for TP53), with annual mammography added from age 40 — MRI is not offered for high-risk-by-family-history alone below the genetic threshold.
- Known gene mutation (BRCA1 / BRCA2, PALB2, others) — annual breast MRI from age 30{nd}49 for BRCA1/BRCA2 carriers, with annual mammography added from age 40, often through a regional genetics centre.
- Previous chest radiotherapy (e.g. childhood lymphoma treatment) — earlier and more intensive screening from 8 years after the radiotherapy3 or from age 25, whichever is later.
If you think you may fall into any of these groups, ask your GP for a referral to a familial-risk clinic. See the family history and risk assessment entries for what’s involved.
Private route Private screening
Private screening offers more flexibility:
- Earlier first mammogram — typically from age 40 (some clinics offer earlier in specific circumstances, with the radiologist’s input on whether that is appropriate).
- Annual rather than every 3 years if preferred1.
- Combined modality — mammogram plus ultrasound, or mammogram plus MRI in higher-risk patients.
- Same-day or next-day reporting rather than the standard NHS turnaround.
Private screening does not replace the NHS programme1 — many patients use both, particularly during their 40s before the NHS programme starts.
The cost depends on the imaging used. A standard private screening mammogram is typically a few hundred pounds; mammogram-plus-ultrasound is more; an MRI screening (used in higher-risk patients) is more again. See fees and insurance for the practice’s specific pricing.
Comparison Mammogram, ultrasound, MRI — what’s the difference?
For screening purposes:
- Mammogram — the gold standard for breast cancer screening in average-risk women. Catches most cancers, including very small ones detectable only by microcalcifications. Less effective in dense breast tissue.
- Ultrasound — useful as an adjunct to mammography in dense breasts, to characterise findings, or in younger women where breast tissue density makes mammography less reliable. Not normally used alone for screening.
- Breast MRI — most sensitive imaging available. Reserved for high-risk women (gene mutations, very strong family history, prior chest radiotherapy) where the additional sensitivity outweighs the higher false-positive rate.
- Tomosynthesis (3D mammography) — a modern variant of mammography that improves cancer detection particularly in dense breasts5. Increasingly the default in private screening; rolling out gradually on the NHS programme.
Limitations What screening does not do
- It does not detect every cancer. Some cancers, particularly fast-growing ones, can develop between screening rounds. If a new lump or change appears between screening mammograms, it should be assessed promptly — do not wait for the next routine appointment.
- It is not a substitute for being aware of your own breasts. Knowing what is normal for you means you notice changes between screens. The NHS phrase “Be Breast Aware” is the operating principle — there is no fixed checklist or timing, just regular awareness.
- It is not appropriate for symptoms. A lump or other change is a reason to see a doctor for assessment, not to wait for a screening appointment. The right pathway is a one-stop breast clinic appointment via a GP referral or self-referral.
At consultation What to discuss with your GP or surgeon
- Should I be in a familial-risk pathway rather than standard screening, given my family history?
- Is private screening worth it before the NHS programme starts, given my personal risk profile?
- What modality is right for me — mammogram alone, or mammogram with ultrasound, or MRI?
- What does an abnormal screen mean — what happens next if something is flagged on a mammogram?
Resources Further reading
- NHS — Breast cancer screening — official NHS programme information.
- NHS — Breast screening: results — what an abnormal screen means and the next steps.
- Breast Cancer Now — Breast screening — patient information including FAQs.
- NICE CG164 — Familial breast cancer — UK guidelines for screening women with family history (clinical-grade detail).
- Breastory: Mammogram · Breast MRI · Risk assessment · BRCA · Family history · One-stop clinic