66 BREAST DISEASE
# BREAST DISEASE
Breast disease is one of the highest-yield surgical topics in MRCS Part A. Examiners test anatomy (especially axillary contents and lymphatic levels), the triple assessment pathway, differentiation of benign from malignant pathology, receptor-driven treatment, and the prognostic significance of nodal status. This lesson works through each in turn.
Surgical anatomy
The breast lies on the anterior chest wall, extending from the 2nd to 6th ribs vertically and from the lateral border of the sternum to the mid-axillary line horizontally. The axillary tail of Spence projects superolaterally through the deep fascia (foramen of Langer) into the axilla — important because cancers can present here and be mistaken for axillary lymphadenopathy.
It sits on pectoralis major, serratus anterior and the upper rectus sheath, separated from pec major by the retromammary space (loose areolar tissue used in implant placement). Cooper's suspensory ligaments tether the gland to the dermis; their malignant infiltration causes the classic skin dimpling and tethering of breast cancer.
Blood supply
| Source | Branch supplying breast |
|---|---|
| Internal thoracic (mammary) artery | Medial perforating branches (largest contribution, ~60%) |
| Axillary artery | Lateral thoracic artery and pectoral branches of thoracoacromial trunk |
| Posterior intercostals | Lateral mammary branches (2nd–4th) |
Venous drainage mirrors the arteries and ultimately enters the axillary, internal thoracic and intercostal veins. The vertebral venous plexus of Batson (valveless) provides a posterior route — explaining axial skeleton metastases.
Lymphatic drainage (very high yield)
- ~75% drains to axillary nodes (mostly the upper outer quadrant)
- ~20% to internal mammary (parasternal) nodes — particularly the medial breast
- A small proportion to supraclavicular, contralateral breast and abdominal nodes
Axillary nodes are surgically divided by pectoralis minor:
| Level | Position relative to pec minor |
|---|---|
| I | Lateral / inferior to pec minor |
| II | Posterior to pec minor (includes Rotter's interpectoral nodes) |
| III | Medial / superior to pec minor (apical) |
An axillary clearance removes levels I and II (and III if grossly involved).
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Nerves of the axilla (at risk during clearance)
| Nerve | Supplies | Damage causes |
|---|---|---|
| Long thoracic (C5–C7) | Serratus anterior | Winged scapula |
| Thoracodorsal (C6–C8) | Latissimus dorsi | Weak shoulder adduction/internal rotation; matters for LD flap reconstruction |
| Intercostobrachial (T2) | Skin of medial arm and floor of axilla | Numb medial upper arm (commonly sacrificed and warned about pre-op) |
Triple assessment
Any discrete breast lump or suspicious symptom is worked up by triple assessment: clinical examination + imaging + tissue sampling. Each is scored 1–5 (concordance below 3 is reassuring; any 4 or 5 mandates biopsy and MDT).
| Score | Clinical (P) | Mammogram (M) | Ultrasound (U) | MRI (R) | Cytology / Core (B) |
|---|---|---|---|---|---|
| 1 | Normal | Normal | Normal | Normal | Inadequate |
| 2 | Benign | Benign | Benign | Benign | Benign |
| 3 | Indeterminate / probably benign | Indeterminate | Indeterminate | Indeterminate | Atypia, probably benign |
| 4 | Suspicious of malignancy | Suspicious | Suspicious | Suspicious | Suspicious of malignancy |
| 5 | Malignant | Malignant | Malignant | Malignant | Malignant |
Choosing the imaging modality
- Ultrasound first if < 35–40 years — younger breasts are dense and mammography lacks sensitivity. USS also differentiates solid from cystic lesions.
- Mammography first if ≥ 35–40 years — picks up microcalcifications (DCIS) and spiculated masses.
- MRI — implants, BRCA surveillance, lobular cancer (multifocal/bilateral), occult primary, equivocal findings.
Tissue sampling
- Core (Tru-cut) biopsy is the gold standard — gives architecture, grade and receptor status (ER, PR, HER2).
- FNA gives cytology only (no architecture, cannot distinguish invasive from in situ disease) — now largely reserved for cyst aspiration and node sampling.
👩⚕️ Mammographic clue: linear / branching microcalcifications = DCIS (especially comedo type). Coarse "popcorn" calcifications = old fibroadenoma. Dystrophic coarse calcifications at a previous surgical site = fat necrosis.
Benign breast disease
| Condition | Typical patient | Key features |
|---|---|---|
| Fibroadenoma | 15–35 y | Firm, smooth, highly mobile "breast mouse"; popcorn calcification if old |
| Simple cyst | 35–50 y (perimenopausal) | Smooth, fluctuant; aspirate clear fluid → discharge if no residual mass and cytology benign |
| Fibrocystic change | 30–50 y | Lumpy, tender, cyclical; dense fibrosis without microcalcification |
| Sclerosing adenosis | 30–50 y | Tender, mobile lump that can mimic cancer; microcalcifications may mimic DCIS |
| Intraductal papilloma | 35–55 y | Single-duct bloody discharge, no mass |
| Duct ectasia | Peri-/post-menopausal | Subareolar duct dilatation; green / creamy "cheese-like" discharge, slit-like nipple retraction |
| Periductal mastitis | Young smoker | Painful peri-areolar inflammation, sterile abscesses, mammillary fistula |
| Lactational mastitis / abscess | Breastfeeding | S. aureus; treat with continued feeding/expression + flucloxacillin ± drainage |
| Fat necrosis | Any age, post-trauma/surgery | Firm irregular lump; coarse dystrophic calcifications and oil cysts |
| Phyllodes tumour | 40–50 y | Rapidly growing, large stromal tumour; leaf-like architecture; can be benign, borderline or malignant — wide excision required |
👩⚕️ Discharge cheat-sheet:
- ➡ Bloody, single duct = intraductal papilloma (or, in older women, malignancy until proven otherwise)
- ➡ Green / creamy, multi-duct = duct ectasia
- ➡ Milky, bilateral = galactorrhoea (prolactinoma, drugs)
- ➡ Purulent = mastitis / abscess
Breast cancer
Breast cancer is the most common malignancy in women in the UK (lifetime risk ~1 in 7) and the second most common cancer killer of women.
Risk factors
Almost every risk factor reflects lifetime oestrogen exposure or genetic predisposition:
- Age, female sex
- Early menarche (< 12), late menopause (> 55), nulliparity, late first pregnancy (> 30)
- HRT (especially combined), prolonged COCP use
- Obesity post-menopause (peripheral aromatisation of androgens to oestrogen in adipose tissue)
- Alcohol; ionising radiation (e.g. mantle radiotherapy for Hodgkin's)
- Family history; BRCA1, BRCA2, TP53 (Li-Fraumeni), PTEN (Cowden)
- Previous breast cancer, LCIS, atypical hyperplasia
- Dense breast tissue
👩⚕️ Exam classic: a thin post-menopausal woman with no family history and a late first pregnancy — the most significant single risk factor is the late first full-term pregnancy (longer unopposed oestrogen exposure, no early protective pregnancy-induced terminal differentiation of breast lobules).
BRCA1 vs BRCA2
| Feature | BRCA1 | BRCA2 |
|---|---|---|
| Chromosome | 17q | 13q |
| Breast cancer | Young onset; often triple-negative | Young onset; ER+ more typical |
| Ovarian cancer | Very high risk (~40%) | Moderate (~15%) |
| Male breast cancer | Slightly raised | Markedly raised |
| Other | Fallopian / peritoneal | Prostate, pancreatic, melanoma |
Both are autosomal dominant tumour suppressor genes.
Histological types
| Type | % of invasive cancers | Notes |
|---|---|---|
| Invasive ductal carcinoma (NST) | ~70–80% | Commonest; spiculated mass on mammogram |
| Invasive lobular carcinoma | ~10–15% | Diffusely infiltrative — often missed on mammography; multifocal and bilateral; metastasises to contralateral breast, peritoneum, GI tract |
| Mucinous, tubular, medullary, papillary | Each < 5% | All have a better prognosis than NST |
| Inflammatory breast cancer | ~1–3% | Lactation-mimic with peau d'orange, no response to antibiotics; dermal lymphatic invasion — aggressive |
| Paget's disease of the nipple | ~1–3% | Eczematous crusting starting on the nipple (not areola — distinguishes from eczema); overlying invasive ductal cancer or DCIS in ~85% |
In situ disease
- DCIS — pre-invasive; confined within basement membrane; commonly detected as microcalcifications on screening mammography; treated to prevent invasion (WLE + radiotherapy, or mastectomy if extensive).
- LCIS — not a precursor in itself but a marker of increased risk of cancer in either breast; managed by surveillance ± risk-reducing surgery in select cases.
Receptor status and prognosis
Every invasive cancer is profiled for ER, PR and HER2.
| Receptor profile | Behaviour | Treatment implication |
|---|---|---|
| ER+ / PR+ / HER2− | Slowest growing, best prognosis | Endocrine therapy |
| ER+ / HER2+ | Intermediate | Endocrine + trastuzumab |
| HER2+ (ER−) | Aggressive but treatable | Trastuzumab |
| Triple negative (ER−/PR−/HER2−) | Worst prognosis; common in BRCA1 | Chemotherapy only (no targeted agent) |
Grading and prognostic index
The Nottingham (modified Scarff-Bloom-Richardson) system scores three histological features I–III: tubule formation, nuclear pleomorphism and mitotic count.
The Nottingham Prognostic Index (NPI) estimates 5-year survival:
> NPI = (0.2 × tumour size in cm) + lymph node score (1–3) + grade (1–3)
- LN score: 0 nodes = 1; 1–3 nodes = 2; > 3 nodes = 3
- < 2.4 excellent; 2.4–3.4 good; > 5.4 poor
👩⚕️ The single most important prognostic factor is axillary nodal status, not size, grade or receptor status. Memorise this — it is a recurring SBA stem.
TNM staging (simplified)
- T1 ≤ 2 cm · T2 2–5 cm · T3 > 5 cm · T4 skin or chest wall involvement (T4d = inflammatory)
- N1 mobile ipsilateral axillary · N2 fixed/matted axillary or internal mammary · N3 infra-/supraclavicular or both axillary + internal mammary
- M1 distant metastasis
Spread
- Local: skin (peau d'orange, tethering), pectoral fascia, chest wall
- Lymphatic: axillary, internal mammary, supraclavicular
- Haematogenous: bone (commonest — mixed lytic/sclerotic), lung, liver, brain
Bone metastases cause hypercalcaemia via osteolysis and tumour-secreted PTHrP — classic stem: confused, vomiting, hypotonic, normal vitals = hypercalcaemia. Cortical destruction predisposes to transverse pathological fractures.
Management
Surgery to the breast
| Wide local excision (WLE) | Mastectomy |
|---|---|
| Solitary, peripheral tumour | Multifocal or central disease |
| Small tumour-to-breast ratio | Large tumour-to-breast ratio |
| DCIS < 4 cm | DCIS > 4 cm |
| Patient choice & able to have radiotherapy | Contraindication to radiotherapy (e.g. prior chest RT, pregnancy) |
| Always followed by adjuvant radiotherapy | RT only if T3/T4 or ≥ 4 positive nodes |
Surgery to the axilla
- Sentinel lymph node biopsy (SLNB) — first-line for clinically and radiologically node-negative axilla. Blue dye + radioisotope identify the first draining node.
- Axillary node clearance (levels I–II ± III) — for biopsy-proven nodal disease or positive SLNB with high burden. Complications: lymphoedema, frozen shoulder, intercostobrachial numbness, long thoracic injury (winged scapula).
Adjuvant therapy
| Therapy | Indication |
|---|---|
| Radiotherapy | After every WLE; after mastectomy if T3/T4 or ≥ 4 nodes |
| Chemotherapy | Triple-negative, HER2+, node-positive, large/high-grade tumours. Regimens: anthracycline + taxane (e.g. FEC-D: 5-FU/epirubicin/cyclophosphamide → docetaxel) |
| Endocrine (5–10 years) | Pre-menopausal ER+ → tamoxifen (SERM); post-menopausal ER+ → aromatase inhibitor (anastrozole, letrozole) |
| Trastuzumab (Herceptin) | HER2+ disease; monitor LVEF (cardiotoxic) |
👩⚕️ Tamoxifen is antagonist in breast but agonist in endometrium and bone — increases endometrial cancer and VTE risk, but protects bone. Aromatase inhibitors block peripheral oestrogen synthesis (useless pre-menopause when the ovary is the source) and accelerate osteoporosis.
NHS Breast Screening Programme
- Women aged 50–71 invited every 3 years for mammography (two views: cranio-caudal + mediolateral oblique).
- High-risk women (BRCA, strong family history, prior mantle radiotherapy) → annual MRI ± mammography from a younger age.
Gynaecomastia
Benign proliferation of the male glandular breast tissue (not just fat — distinguishing from pseudogynaecomastia). Driven by an oestrogen : androgen imbalance.
Causes (high yield):
- Physiological — neonatal, pubertal, senile (the three peaks of life — answer for "most likely cause")
- Hypogonadism — Klinefelter's (47,XXY), mumps orchitis
- Tumours secreting hCG — testicular (seminoma, NSGCT), bronchial, hepatic
- Endocrine — hyperthyroidism, adrenal tumours
- Systemic — cirrhosis (reduced oestrogen clearance), CKD on haemodialysis
- Drugs (mnemonic: "DISCO"): Digoxin, Isoniazid/cimetidine, Spironolactone, Cannabis/CCBs, Oestrogens — plus PPIs, finasteride, anabolic steroids
[Image: MCQs banner]
Test yourself
A 25-year-old woman has a single mobile breast lump. Most appropriate first imaging?
- ((Ultrasound::☑️ Dense glandular breast under 35–40 — USS distinguishes solid vs cystic better than mammography.))
- ((Mammography::First-line over 40; misses lesions in dense young breasts.))
- ((MRI::Reserved for implants, BRCA surveillance, occult primary or equivocal findings.))
- ((Core biopsy::Comes after imaging, not before.))
A 48-year-old BRCA1-positive woman presents with a firm breast lump. First-line imaging?
- ((Mammogram::☑️ Over 40 → mammography first; core biopsy follows if suspicious.))
- ((Ultrasound::Adjunct in this age group, not first-line for a discrete lump.))
- ((MRI::Used for BRCA surveillance, not first-line workup of a clinical lump.))
- ((PET-CT::Staging tool, not diagnostic.))
A 25-year-old with bilateral implants and strong family history presents with a lump. Next investigation?
- ((MRI::☑️ Implants obscure mammography; BRCA-type risk and prosthesis concerns → straight to MRI.))
- ((Mammography::Compressing implants risks rupture and poor sensitivity around prosthesis.))
- ((Ultrasound::Reasonable in low-risk implant patients, but not here given strong family history.))
- ((CT chest::No role in breast lump assessment.))
👩⚕️ Default to MRI when implants + high-risk genetics coincide.
A lump is palpable and seen on mammography. Next best step?
- ((Core (Tru-cut) biopsy::☑️ Gold standard — gives architecture, grade and ER/PR/HER2 status.))
- ((FNA::Cytology only; cannot separate invasive from in situ disease.))
- ((Excisional biopsy::Outdated as first sampling; reserved for non-diagnostic core.))
- ((MRI::Adjunct, not the tissue diagnosis step.))
A 36-year-old woman has bloody single-duct nipple discharge with no mass. Most likely diagnosis?
- ((Intraductal papilloma::☑️ Premenopausal, single-duct bloody discharge, no mass — classic.))
- ((Duct ectasia::Multi-duct green/creamy discharge in peri-menopausal women.))
- ((Breast cancer::Possible in older patients; less likely without mass at 36, but always exclude.))
- ((Fibroadenoma::Painless mobile lump; does not cause discharge.))
A 60-year-old has creamy, cheese-like nipple discharge and slit-like nipple retraction. Diagnosis?
- ((Duct ectasia::☑️ Subareolar duct dilatation with periductal chronic inflammation — multi-duct creamy discharge.))
- ((Intraductal papilloma::Single-duct bloody discharge in younger women.))
- ((Breast cancer::Pulls nipple inwards but discharge usually bloody or absent; biopsy mandatory if doubt.))
- ((Fibroadenoma::Mobile firm lump in young women; no discharge.))
A 30-year-old nulliparous smoker has recurrent peri-areolar redness with sterile greenish discharge. Diagnosis?
- ((Periductal mastitis::☑️ Smoking → squamous metaplasia of lactiferous ducts → obstruction and sterile inflammation.))
- ((Duct ectasia::Peri-/post-menopausal, not young smokers.))
- ((Lactational abscess::Requires breastfeeding and S. aureus.))
- ((Inflammatory breast cancer::No mass and recurrent picture make malignancy less likely, but exclude if persistent.))
A 45-year-old has discrete nodules; histology shows dense fibrous tissue, no microcalcifications. Diagnosis?
- ((Fibrocystic change::☑️ Lumpy, cyclical, fibrosis without microcalcification.))
- ((Sclerosing adenosis::Often shows microcalcifications mimicking DCIS.))
- ((Fibroadenoma::Discrete mobile mass, not diffuse fibrosis.))
- ((Phyllodes tumour::Large rapidly growing stromal lesion with leaf-like architecture.))
A 35-year-old had a breast biopsy 10 years ago and now has three areas of calcification at the scar. Diagnosis?
- ((Fat necrosis::☑️ Coarse dystrophic calcifications post trauma/surgery; oil cysts on imaging.))
- ((Fibroadenoma::Popcorn calcifications, not at a surgical scar.))
- ((Recurrent malignancy::Microcalcifications, spiculated mass — not dystrophic clusters at scar.))
- ((Inflammatory cancer::Skin erythema and peau d'orange, not asymptomatic calcifications.))
A woman has a normal mammogram now and 2 years ago, but ultrasound shows an abnormality. Most likely diagnosis?
- ((Invasive lobular carcinoma::☑️ Diffuse infiltrative growth — no dense mass on mammography; often multifocal/bilateral.))
- ((Invasive ductal carcinoma::Usually visible as spiculated mass with microcalcifications.))
- ((Fat necrosis::Visible coarse calcifications on mammography.))
- ((Phyllodes tumour::Large palpable mass, easily seen on imaging.))
👩⚕️ Lobular cancer is the classic "mammographically occult" tumour — favours MRI for full assessment.
A 33-year-old lactating woman has breast swelling and redness not responding to antibiotics. Diagnosis?
- ((Inflammatory breast cancer::☑️ Persistent peau d'orange unresponsive to antibiotics; dermal lymphatic invasion.))
- ((Lactational mastitis::Would respond to flucloxacillin and continued drainage.))
- ((Breast abscess::Fluctuant collection on USS; drainage curative.))
- ((Duct ectasia::Peri-menopausal, not lactational.))
A 66-year-old has a crusty lesion on the nipple with no underlying mass. Diagnosis?
- ((Paget's disease of the nipple::☑️ Starts on the nipple (not areola); punch biopsy shows Paget cells in epidermis.))
- ((Eczema::Starts on areola and spares the nipple — opposite distribution.))
- ((Basal cell carcinoma::Rare on nipple; pearly rolled edge rather than eczematous crust.))
- ((Inflammatory breast cancer::Diffuse erythema and peau d'orange of the whole breast.))
A woman has a breast mass with eczema of the nipple. Apart from mammography, next investigation?
- ((Punch biopsy of the nipple skin::☑️ Confirms Paget cells; ~85% have underlying DCIS or invasive cancer.))
- ((Skin swab::No microbiological cause; misses the diagnosis.))
- ((Topical steroids::Will mask Paget's by transiently improving the rash.))
- ((MRI alone::Useful adjunct but does not give histological diagnosis.))
A woman has a breast lump with skin tethering and nipple retraction. Diagnosis?
- ((Breast cancer::☑️ Tumour fibrosis pulls on Cooper's ligaments → tethering; ductal invasion retracts nipple.))
- ((Fat necrosis::Can tether but usually post-trauma and stable.))
- ((Duct ectasia::Slit-like retraction without a hard tethered mass.))
- ((Fibroadenoma::Mobile, smooth, no skin changes.))
A discrete lump shows histology of apocrine metaplasia, epithelial overgrowth and leaf-like papillary projections. Diagnosis?
- ((Phyllodes tumour::☑️ Leaf-like stromal architecture; rapidly growing; needs wide excision.))
- ((Fibroadenoma::Pericanalicular/intracanalicular growth without leaf-like pattern.))
- ((DCIS::Confined within ducts, not stromal leaf-like architecture.))
- ((Invasive ductal carcinoma::Infiltrative malignant ducts, not stromal leaf-like growth.))
A thin post-menopausal woman with menarche at 14 and first child at 40 develops breast cancer. Most significant risk factor?
- ((Late first full-term pregnancy::☑️ Prolonged unopposed oestrogen exposure; no early pregnancy-induced lobular differentiation.))
- ((Menarche at 14::Average age — not a strong risk factor.))
- ((Previous lactational abscess::No causal association.))
- ((Body habitus::Low BMI is not a risk factor post-menopause (high BMI is).))
Defective gene in hereditary breast cancer?
- ((BRCA1::☑️ Chromosome 17 tumour suppressor; triple-negative breast and ovarian cancer.))
- ((TP53::Li-Fraumeni — sarcomas, leukaemia, adrenocortical cancer.))
- ((MYC::Oncogene amplified in many tumours; not a primary breast-cancer susceptibility gene.))
- ((STK11::Peutz-Jeghers syndrome.))
- ((APC::Familial adenomatous polyposis.))
A 43-year-old has had WLE + SLNB. Which factor carries the most prognostic weight?
- ((Nodal status::☑️ Strongest independent predictor of survival in breast cancer.))
- ((Tumour size::Important but secondary to nodal status.))
- ((Grade::Contributes to NPI but less weight than nodes.))
- ((ER status::Guides treatment; modest prognostic effect.))
- ((Mitotic count::One component of grade only.))
Which receptor profile carries the best prognosis?
- ((ER+ / PR+ / HER2−::☑️ Hormone responsive, slow growing, lowest recurrence.))
- ((ER+ / PR+ / HER2+::Intermediate — HER2+ adds aggression despite hormone responsiveness.))
- ((ER− / PR− / HER2−::Triple-negative — worst prognosis.))
- ((ER− / PR− / HER2+::Aggressive, though trastuzumab improves outcome.))
A 75-year-old has a 6 cm breast tumour with no skin/chest wall involvement but mobile axillary nodes. Clinical stage?
- ((T3 N1 M0::☑️ > 5 cm = T3; mobile ipsilateral nodes = N1; no distant disease = M0.))
- ((T3 N2 Mx::N2 requires fixed/matted nodes; Mx not used when no distant disease suspected.))
- ((T4 N1 M0::T4 needs skin or chest wall involvement.))
- ((T3 N3 M0::N3 requires supra-/infraclavicular or combined axillary + internal mammary nodes.))
A woman with metastatic breast cancer presents confused, nauseated and hypotonic with normal observations. Most likely contributor?
- ((Hypercalcaemia::☑️ Osteolytic bone metastases and PTHrP secretion; "stones, bones, groans, psychic moans".))
- ((Hyponatraemia::Possible but does not classically cause hypotonia with normal vitals.))
- ((Hypoglycaemia::No diabetic/insulin context given.))
- ((Brain metastasis alone::Would typically show focal neurology or seizures.))
A woman with metastatic breast cancer fractures her humerus catching a bus. Likely fracture pattern?
- ((Transverse::☑️ Pathological fractures through cortical bone weakened by metastasis are typically transverse.))
- ((Spiral::Torsional injury in normal bone.))
- ((Oblique::Angulated force on normal bone.))
- ((Greenstick::Incomplete paediatric fracture.))
Bone scan shows a lytic femoral lesion in a 55-year-old woman. Most likely primary?
- ((Breast cancer::☑️ Common in women; classically mixed lytic/sclerotic but ER-negative disease can be purely lytic.))
- ((Lung cancer::Typically lytic but less common than breast in women.))
- ((Bladder TCC::Bone metastases uncommon.))
- ((Thyroid cancer::Follicular variant causes lytic lesions but far rarer overall.))
A breast cyst aspirate is clear and cytology is reassuring with no residual mass. Next step?
- ((Discharge::☑️ Concordant triple assessment benign — no further action needed.))
- ((Repeat USS in 6 weeks::Unnecessary in fully reassured triple assessment.))
- ((Excision biopsy::Only if bloodstained aspirate, residual mass or recurrence.))
- ((Tamoxifen::No role in benign cysts.))
A 16-year-old boy has gynaecomastia. Most likely cause?
- ((Physiological (pubertal)::☑️ Transient oestrogen surge in puberty; resolves spontaneously.))
- ((Klinefelter's::Possible but presents with small firm testes, tall stature, infertility.))
- ((Testicular tumour::Always exclude on examination; rare overall.))
- ((Liver disease::Uncommon at this age without other stigmata.))
A middle-aged man presents with gynaecomastia. Which drug is the most likely cause?
- ((Spironolactone::☑️ Anti-androgen effect; classic exam answer.))
- ((Metformin::No effect on breast tissue.))
- ((Paracetamol::No association.))
- ((Atorvastatin::No association.))
- ((Ibuprofen::No association.))
👩⚕️ Drug causes — DISCO: Digoxin, Isoniazid/cimetidine, Spironolactone, Cannabis/CCBs, Oestrogens (+ PPIs, finasteride).
Which is a recognised tumour marker for breast cancer?
- ((CA 15-3::☑️ Used to monitor recurrence in metastatic disease; CEA also raised.))
- ((CA 72-9::Gastric cancer.))
- ((5-HIAA::Carcinoid syndrome.))
- ((Chromogranin A::Neuroendocrine tumours.))
- ((CA 19-9::Pancreatic / biliary cancer.))
Revision summary
- Anatomy: 2nd–6th rib, sternum to mid-axillary line; tail of Spence pierces deep fascia. Blood supply: internal thoracic, lateral thoracic, posterior intercostals.
- Lymphatics: ~75% to axilla. Levels I/II/III defined by pec minor (lateral / posterior / medial).
- Axillary nerves: long thoracic (winged scapula), thoracodorsal (LD flap), intercostobrachial (medial arm numbness).
- Triple assessment: clinical + imaging + biopsy, all scored 1–5. USS < 35–40 y; mammography ≥ 35–40 y; MRI for implants/BRCA/lobular. Core biopsy is gold-standard tissue diagnosis.
- Discharge: bloody single duct → papilloma; green/creamy multi-duct → duct ectasia; periductal mastitis in young smokers.
- Calcifications: linear/branching microcalcifications → DCIS; popcorn → old fibroadenoma; dystrophic at scar → fat necrosis.
- Commonest cancer: invasive ductal (70–80%). Lobular = multifocal, bilateral, mammographically occult.
- Receptors: ER+/PR+/HER2− best; triple negative worst. Nodal status = strongest prognostic factor.
- BRCA1 (chr 17) — triple-negative + ovarian; BRCA2 (chr 13) — male breast + pancreatic.
- Surgery: WLE (+ radiotherapy always) vs mastectomy (multifocal, large:breast ratio, central). SLNB if clinically node-negative; clearance if positive.
- Adjuvant: tamoxifen (pre-meno ER+), anastrozole (post-meno ER+), trastuzumab (HER2+), anthracycline + taxane chemo for high-risk/triple-negative.
- Screening: 50–71 y mammogram every 3 years.
- Metastases: bone (mixed), lung, liver, brain → hypercalcaemia, transverse pathological fractures.
- Gynaecomastia drugs (DISCO): Digoxin, Isoniazid/cimetidine, Spironolactone, Cannabis/CCBs, Oestrogens.