Breast Care A-Z · Procedure · RRM

Risk-reducing mastectomy

also: prophylactic mastectomy, preventive mastectomy, bilateral risk-reducing mastectomy, BRRM

A risk-reducing (prophylactic) mastectomy removes healthy breast tissue to substantially lower the chance of developing breast cancer in women at high genetic risk. You may have a confirmed high-risk mutation (BRCA1, BRCA2, PALB2, or other) and be considering surgery, or be reading to understand what the operation involves.

Quick answers

At what age should risk-reducing mastectomy be considered?

There is no fixed age. Many BRCA1 carriers consider surgery in their late 20s to mid-30s, BRCA2 carriers a few years later. The decision balances the rising lifetime risk (which accelerates from the mid-30s for BRCA1) against family-planning considerations and personal readiness.

Do I have to have surgery if I am BRCA-positive?

No. Surgery is one option among three (alongside surveillance and chemoprevention). Many BRCA carriers choose surveillance for years before considering surgery, or never proceed to surgery. The decision is yours.

Can I have surgery on one breast first and the other later?

Bilateral surgery is the standard, because the risk is bilateral. Staged unilateral surgery is occasionally chosen, but it introduces a period of asymmetry and a second recovery.

SURGERY · RISK REDUCTION PLATE L risk-reducing mastectomy prophylactic mastectomy · RRBM surgical removal of healthy breast tissue to substantially reduce future cancer risk in genetically predisposed individuals Encyclopaedia of the Breast · Breastory · clinically authored FIG 01 Bilateral Mastectomy — Anatomical Diagram pectoralis major (L) pectoralis major (R) BRCA surgical decision NSM option skin-sparing envelope skin-sparing envelope Callouts i bilateral mastectomy incisions (dashed ellipses) ii skin-sparing technique — breast envelope preserved iii pectoral fascia plane — dissection plane below breast iv immediate reconstruction option available at same operation v nipple-areola complex: may be preserved (NSM) or removed depending on risk Incision lines shown as dashed ellipses. BRCA gene symbol (helix) indicates hereditary risk pathway leading to surgical decision. NSM = nipple-sparing mastectomy. Bilateral procedure shown. Pectoralis major preserved in skin-sparing technique. Reconstruction (implant or autologous flap) may be immediate or delayed. Residual breast tissue risk remains: surveillance of chest wall recommended post-RRM. RRBM = risk-reducing bilateral mastectomy. Indications · BRCA1/2 carrier (>25–30% lifetime risk) · Strong family history (NICE high-risk) · Prior chest RT (Hodgkin's lymphoma) · TP53/Li–Fraumeni syndrome · Personal preference after counselling NICE NG151 criteria apply Decision Process 1. Genetic counselling (mandatory first) 2. Risk calculation — Tyrer–Cuzick / IBIS 3. MDT discussion (genetics, surgery, oncology, psychology) 4. Informed consent + reflection period Min. 3-month reflection recommended FIG 02 BRCA Carrier vs High-Risk Non-Carrier Feature BRCA1/2 Confirmed High-Risk Non-Carrier Mutation status BRCA1/2 pathogenic variant No mutation found Lifetime risk ~70% 25–30% RRM indication Yes (NICE NG151) Discuss at MDT Risk reduction ~90–95% ~90% Timing After family complete Similar Surveillance alternative MRI from age 30 Annual mammogram Chemoprevention Tamoxifen option Tamoxifen / anastrozole Psychosocial support Essential Essential RRSO also discussed Yes (oophorectomy) Not usually Reconstruction Discussed simultaneously Yes Reconstruction timing Immediate or delayed Immediate or delayed FIG 03 Benefits vs Risks of Risk-Reducing Mastectomy Outcome Benefit Risk / Consideration Cancer reduction ~90–95% Residual 2–5% risk Mortality Significant reduction Not zero Reconstruction Wide options available Staged surgery possible Recovery 4–8 weeks typical Longer if flap reconstruction Psychological Reduced cancer anxiety Body image change Breastfeeding N/A (prophylactic) No longer possible after RRM Sensation Chest wall preserved Chest sensation changed permanently Regret Low if well counselled 5–10% report regret Fertility Not affected by mastectomy Reconstruction timing consideration FIG 04 RRM Pathway — 6 Steps Step 1 Referral to genetics service Step 2 BRCA test result Step 3 Genetic counselling (min 3 months reflection) Step 4 MDT + surgical discussion Step 5 Risk-reducing bilateral mastectomy ± recon Step 6 Surveillance of residual risk Timing of reconstruction discussed at step 4; fertility and RRSO (if BRCA) addressed simultaneously at MDT. Psychological support offered throughout pathway. FIG 05 Procedure Variants BRCA1-associated RRM Highest-risk indication ~65–80% lifetime risk BRCA2-associated RRM 45–70% lifetime risk Also consider RRSO TP53 / Li–Fraumeni Very high lifetime risk RT avoided Skin-sparing RRM Envelope preserved Optimises recon result Nipple-sparing RRM NSM if nipple low-risk Improving cosmesis Bilateral + DIEP flap Immediate autologous reconstruction NSM = nipple-sparing mastectomy. DIEP = deep inferior epigastric perforator flap. Variant chosen at MDT based on risk level, anatomy and preference. All variants aim for complete glandular excision. Residual native breast tissue risk remains regardless of technique. Implant-based immediate reconstruction also widely used as alternative to autologous flap. Choice of reconstruction does not alter the oncological risk reduction achieved by RRM. FIG 06 Key Statistics ~90–95% cancer risk reduction [1] Hartmann et al. NEJM 1999 ~1 in 400 carry BRCA mutation [2] population estimate <10% regret if well counselled [3] Hooker et al. Genet Med 2014 ~40% mastectomy patients choose recon [4] Metcalfe et al. Ann Surg Oncol 2015 FIG 07 References 1. NICE NG151. Familial breast cancer. 2023. 2. Hartmann LC et al. Risk-reducing mastectomy. NEJM 1999;340:77. 3. Hooker GW et al. Psychosocial outcomes after RRM. Genet Med 2014. 4. Metcalfe KA et al. Satisfaction after bilateral RRM. Ann Surg Oncol 2015. 5. Evans DGR et al. BRCA1/2 risk management. Lancet Oncol 2021. Clinically authored by Dr Fiona Tsang-Wright , FRCS (Gen Surg) GMC 4549831 · ORCID 0000-0003-4801-026X
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Definition
A risk-reducing mastectomy is the surgical removal of healthy breast tissue, almost always bilateral and almost always with immediate reconstruction, performed to reduce the future risk of breast cancer in patients with substantially raised genetic or family-history risk.
≈ 90% Reduction in breast cancer risk after bilateral prophylactic mastectomy 1

Common questions The questions patients ask first

At what age should risk-reducing mastectomy be considered?
There is no fixed age. Many BRCA1 carriers consider surgery in their late 20s to mid-30s, BRCA2 carriers a few years later23. The decision balances the rising lifetime risk (which accelerates from the mid-30s for BRCA1) against family-planning considerations and personal readiness.
Do I have to have surgery if I am BRCA-positive?
No. Surgery is one option among three (alongside surveillance and chemoprevention)3. Many BRCA carriers choose surveillance for years before considering surgery, or never proceed to surgery. The decision is yours.
Can I have surgery on one breast first and the other later?
Bilateral surgery is the standard, because the risk is bilateral1. Staged unilateral surgery is occasionally chosen, but it introduces a period of asymmetry and a second recovery.
Will my insurance cover it?
Most UK private medical insurers cover risk-reducing mastectomy and reconstruction when there is a confirmed high-risk genetic mutation or formally documented very-high-risk family history. Pre-authorisation requires the genetic test result or risk-assessment documentation.
What if cancer is found in the mastectomy specimen?
This happens in a small percentage of risk-reducing mastectomies — typically a small, early cancer that imaging had not detected8. The case is reviewed at MDT and any additional treatment is decided then. The reconstruction is not affected.

A risk-reducing mastectomy is the surgical removal of healthy breast tissue, almost always bilateral and almost always with immediate reconstruction, performed to reduce the future risk of breast cancer in patients with substantially raised genetic or family-history risk.

Risk-reducing mastectomy is one of three reasonable approaches for high-risk patients — alongside enhanced surveillance and chemoprevention3. It reduces breast cancer risk by approximately 90–95% in BRCA carriers18. The decision is personal, rarely urgent, and made over months rather than weeks; many patients choose it, many choose surveillance, and both are reasonable.

Orientation Why you might be reading about this

You may have a confirmed high-risk genetic mutation (BRCA1, BRCA2, PALB2, or other) and be considering surgical risk reduction, or you are reading to understand what the operation involves. Risk-reducing mastectomy is one of the more consequential elective operations in modern medicine — performed on healthy tissue, in patients who feel well — and it is taken seriously. This page explains what the operation is, who it is offered to, and how it sits alongside the alternatives.

Related terms: Mastectomy · BRCA · Family history · DIEP flap

Suitability Who is offered risk-reducing mastectomy

Risk-reducing mastectomy is considered when the lifetime risk of breast cancer is sufficiently high that the operation offers meaningful protection over surveillance alone. The most common groups are:

  • BRCA1 carriers — lifetime risk approximately 70–80%2.
  • BRCA2 carriers — lifetime risk approximately 60–70%2.
  • PALB2 carriers — lifetime risk approximately 35–55%36.
  • TP53 (Li-Fraumeni) carriers — substantially raised risk, often presenting at younger ages.
  • CHEK2 and ATM carriers in selected high-risk family contexts.
  • Patients with a strong family history but no identified gene, where formal risk assessment puts the lifetime risk over ~30%3.

For more on the genetic side, see BRCA and family history.

A separate situation is contralateral risk-reducing mastectomy — removing the unaffected breast in a patient who has had cancer in the other breast. The decision-making is different and is covered separately — see contralateral risk-reducing mastectomy.

Risk reduction How much risk reduction does it actually provide

The figures most commonly used in patient consultations:

  • ~90–95% reduction in breast cancer risk in BRCA1/BRCA2 carriers18.
  • The residual risk reflects the small amount of breast tissue that cannot be safely removed, leaving a residual lifetime risk of roughly 2-5% in BRCA carriers, leaving a residual lifetime risk of roughly 2–5% in BRCA carriers, without compromising the skin envelope or chest wall.
  • Risk reduction does not translate one-for-one into mortality reduction, because surveillance also catches many cancers at curable stages. The all-cause mortality benefit is real but smaller than the cancer-incidence reduction8.

For moderate-penetrance mutations (PALB2, CHEK2, ATM) and family-history-based high risk, the absolute risk reduction is proportionally less because the starting risk is lower — but the relative reduction is similar.

Alternatives The alternatives

Risk-reducing mastectomy is one of three options for high-risk patients. The others are:

Enhanced surveillance

Annual breast MRI from age 30 (sometimes 25), often with annual mammography from age 403. Surveillance does not prevent cancer; it detects it early. Most cancers caught on surveillance in high-risk patients are early-stage and treatable.

Chemoprevention

Tamoxifen (5 years, in pre-menopausal patients) and anastrozole (first line, unless osteoporosis) or raloxifene (in post-menopausal patients) reduce breast cancer incidence by approximately 30–50% in high-risk patients45. They have side effects but are an option some patients prefer over surgery.

Continuing as you are

For some patients, the right answer at this point in life is to continue with surveillance and revisit surgery later. There is no clinical urgency to act before you have weighed the options.

The procedure What the operation involves

  • Bilateral mastectomy with immediate reconstruction in almost all cases7.
  • Skin-sparing or nipple-sparing technique preferred where the anatomy allows it, to give the most natural-looking result7.
  • Reconstruction — implant-based (1–2 nights in hospital) or autologous (DIEP flap, 4–5 nights).
  • Revision operation at 6–12 months for symmetry, scar refinement, or — where the nipple was not preserved — nipple reconstruction.
  • Sentinel lymph node biopsy is not routinely done because there is no diagnosed cancer7.

For the practice’s full pathway, see risk-reducing mastectomy service page.

What’s preserved What is preserved and what is not

Honesty about outcomes is important:

  • Sensation in the chest wall is significantly reduced. Even with nipple-sparing technique, sensation in the nipple is usually reduced and sometimes absent.
  • Breastfeeding is no longer possible after risk-reducing mastectomy.
  • Cosmetic outcome is usually good but is not identical to natural breasts.
  • Future surveillance of the chest wall is still recommended (clinical examination); the residual breast tissue is small but not zero.

These are not reasons to avoid the operation — they are reasons to make the decision with full information.

Beyond the breast The ovarian-cancer conversation

For BRCA1, BRCA2, and PALB2 carriers, ovarian cancer risk is also raised2. Risk-reducing salpingo-oophorectomy (removal of fallopian tubes and ovaries) is usually recommended between ages 35-40 for BRCA1 and 40-45 for BRCA2. PALB2 carriers have a moderately raised ovarian risk (~5%); RRSO timing is individualised and typically later than for BRCA carriers38. It is performed by a gynaecological surgeon and is part of the broader risk-management plan, separate from the breast operation.

At consultation What to discuss at consultation

If risk-reducing mastectomy is being considered:

  • Risk reduction figures specific to your gene and your age.
  • Alternatives — surveillance, chemoprevention — and how they compare to surgery.
  • The operation itself — type of mastectomy, reconstruction options, recovery, outcomes.
  • Sensation, breastfeeding, and other practical implications.
  • Timing — most patients consider this decision over months. There is no clinical urgency unless a high-risk result has just been identified, and even then, weeks or a few months of consideration are reasonable.
  • The gynaecological side — risk-reducing salpingo-oophorectomy, where applicable.

A second-opinion consultation is a usual way to review whether risk-reducing mastectomy is the right step for you.

Resources Further reading

Sources & guidance

Every figure on this page is anchored to a published source. Tap a number in the text or below to jump to the reference.

  1. cohort Hartmann LC, Sellers TA, Schaid DJ, et al. Efficacy of bilateral prophylactic mastectomy in women with a family history of breast cancer. New England Journal of Medicine. 1999 ;340(2):77-84 doi:10.1056/NEJM199901143400201 Cited for: ~90% breast cancer risk reduction from bilateral prophylactic mastectomy in high-risk women.
  2. cohort Kuchenbaecker KB, Hopper JL, Barnes DR, et al. Risks of Breast, Ovarian, and Contralateral Breast Cancer for BRCA1 and BRCA2 Mutation Carriers. JAMA. 2017 ;317(23):2402-2416 doi:10.1001/jama.2017.7112 Cited for: Lifetime breast cancer risk in BRCA1 (~72%) and BRCA2 (~69%) carriers; ovarian cancer risk; contralateral risk.
  3. guidance National Institute for Health and Care Excellence (NICE). Familial breast cancer: classification, care and managing breast cancer and related risks in people with a family history. NICE clinical guideline CG164. London: NICE. 2019 https://www.nice.org.uk/guidance/cg164 Cited for: Risk thresholds (population/moderate/high), surveillance schedules, genetic testing criteria, chemoprevention guidance.
  4. meta analysis Early Breast Cancer Trialists' Collaborative Group (EBCTCG). Relevance of breast cancer hormone receptors and other factors to the efficacy of adjuvant tamoxifen: patient-level meta-analysis of randomised trials. The Lancet. 2011 ;378(9793):771-784 doi:10.1016/S0140-6736(11)60993-8 Cited for: Magnitude and durability of tamoxifen benefit in ER-positive breast cancer; ~50% reduction in recurrence over 5 years.
  5. rct Cuzick J, Sestak I, Forbes JF, et al. Anastrozole for prevention of breast cancer in high-risk postmenopausal women (IBIS-II): an international, double-blind, randomised placebo-controlled trial. Lancet. 2014 ;383(9922):1041-1048 doi:10.1016/S0140-6736(13)62292-8 Cited for: IBIS-II: anastrozole reduces breast cancer incidence in high-risk postmenopausal women — primary chemoprevention evidence.
  6. cohort Antoniou AC, Casadei S, Heikkinen T, et al. Breast-cancer risk in families with mutations in PALB2. New England Journal of Medicine. 2014 ;371(6):497-506 doi:10.1056/NEJMoa1400382 Cited for: PALB2 lifetime breast cancer risk (~33-58%); landmark cohort establishing PALB2 as a high-penetrance gene.
  7. guideline National Institute for Health and Care Excellence. Early and locally advanced breast cancer: diagnosis and management (NG101). NICE. 2018 ;Last updated 2024 https://www.nice.org.uk/guidance/ng101 Cited for: UK guideline for surgical management of breast cancer including pathway for risk-reducing operations and reconstruction.
  8. cohort Domchek SM, Friebel TM, Singer CF, et al. Association of risk-reducing surgery in BRCA1 or BRCA2 mutation carriers with cancer risk and mortality. JAMA. 2010 ;304(9):967-975 doi:10.1001/jama.2010.1237 Cited for: Risk-reducing mastectomy and salpingo-oophorectomy in BRCA carriers: cancer-incidence reduction and all-cause mortality benefit; occult cancer detection rate.