Cancer and Family History
When a pattern of cancer in a family suggests an inherited predisposition.
Last revised
Key takeaways
- Most cancers: are not caused by an inherited gene fault
- Concerning pattern: several close relatives, young ages, or the same cancer type
- Most useful single change: Draw up a family tree with ages at diagnosis before the appointment.
- Commonest mistake: Assuming any cancer in the family means inherited risk.
- See a doctor if any of the signs under "When to get help" below apply to you.
Why it matters
Most cancer is not inherited, and identifying the minority that is changes screening and prevention substantially.
The numbers, in one place
| Measure | Figure |
|---|---|
| Most cancers | are not caused by an inherited gene fault |
| Concerning pattern | several close relatives, young ages, or the same cancer type |
| Examples | BRCA1 and BRCA2, Lynch syndrome |
| Referral | to a genetics service, via a GP |
| Result | may change screening age, frequency and prevention options |
What helps
- Draw up a family tree with ages at diagnosis before the appointment
- Include both sides of the family
- Ask your GP about genetics referral if the pattern is concerning
- Tell relatives if a fault is found; it affects them too
What to avoid
- Assuming any cancer in the family means inherited risk
- Direct-to-consumer genetic tests as a substitute for clinical genetics
- Delaying screening while awaiting genetic results
Where to go next
- Cancer and Family History at a Glance
- Cancer and Family History: What Published Guidance Supports
- The Evidence on Cancer Treatment Side Effects, Without the Hype
- Talking About Cancer: What Published Guidance Supports
When to get help
See a GP about genetics referral if several close relatives have had cancer, if any were diagnosed under 50, if the same cancer appears repeatedly, or if a relative has a known gene fault. Continue to report symptoms promptly regardless of family history or genetic results.
Where this comes from
- NICE — Familial breast cancer
- Cancer Research UK — family history and inherited cancer genes
How this page was put together
Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarised or generalised beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.
Medical disclaimer
This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to a GP, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 999.