Breast Cancer

Meet the patient

A 54-year-old woman found a painless lump in her right upper outer quadrant while showering a month ago. It is hard, irregular, and does not move when she lifts her arm. Her aunt had breast cancer at 48. She has not told her husband, because she is frightened of the answer.[3]

Two questions decide her pathway, and they decide every breast lump: is this cancer? (triple assessment answers it, 98% of the time) and if it is, what is its subtype? (the receptors choose every drug she will take). Hold those two questions and the rest of the topic arranges itself.[3]

One breast, three classifications — but only the subtype prescribes

Breast cancer is classified on three axes, and only the molecular one writes the prescription. Anatomical extent splits in situ from invasive; histology splits ductal from lobular and the special types; the molecular subtype — ER, PR, HER2, Ki-67 — is the axis that decides every systemic drug.[3]

The two histogenetic families come straight from the anatomy. The breast is a modified sweat gland of 15 to 20 lobes, each draining through a ductal tree to a lactiferous duct at the nipple; ductal cancers (the great majority) and lobular cancers arise from those two linings. Most tumours sit in the upper outer quadrant — about 40% — because that quadrant carries the most glandular tissue. Lymph drains first to the axillary nodes (levels I to III), then to the supraclavicular and internal mammary chains.[3]

The clinicopathological groups an examiner expects you to separate:[3]

[3]

The molecular subtype is the whole systemic plan

Four subtypes, four different drug lists — get this table right and you have half the viva. The subtype comes from immunohistochemistry for ER, PR and HER2 (HER2 equivocals confirmed by in-situ hybridisation) plus a proliferation marker, usually Ki-67.[1]

[1]

The classic trap: receptor status is not a refinement you add later — it is the plan. A registrar who books surgery without ER, PR, HER2 and Ki-67 on the core biopsy has nothing to say at the MDT. Order the receptors on the biopsy, every time.[1]

Etymology for viva gold: mastectomy is from Greek mastos, "breast", plus ektomē, "a cutting out" — the operation is named for what it removes, not how. Paget disease of the nipple carries Sir James Paget's name; he described the nipple eruption in 1874 and predicted, correctly, that an underlying cancer would follow within two years.[3]

How common, who, why — the 1-in-8 and the oestrogen thread

Breast cancer is the commonest cancer in women worldwide — about a quarter of all female cancers, lifetime risk roughly 1 in 8 in developed countries, and the leading cause of cancer death in women in many low- and middle-income countries. Peak incidence in Western populations sits between 50 and 70, median age around 62.[3]

[3]

Risk factors cluster in three groups. The genetic group is the most examinable: germline BRCA1 (chromosome 17q21) and BRCA2 (chromosome 13q12) mutations account for 5 to 10% of all breast cancers, conferring 55 to 72% (BRCA1) and 45 to 69% (BRCA2) lifetime risk. BRCA1 tumours are characteristically high-grade, triple-negative and basal-like; BRCA2 tumours are more often ER-positive. The rarer syndromes — Li-Fraumeni (TP53), Cowden (PTEN), Peutz-Jeghers (STK11), hereditary diffuse gastric cancer (CDH1) — each carry their own risk.[3]

Everyone forgets: the hormonal and reproductive factors are all one mechanism — cumulative lifetime oestrogen exposure to the breast epithelium. Early menarche, late menopause, nulliparity, late first pregnancy, short breastfeeding, and exogenous hormones (combined HRT; a small transient rise from the combined pill) all push the same dial. Postmenopausal obesity matters because adipose aromatises androgens to oestrogen; alcohol and smoking are independent add-ons.[3]

The third group is prior breast disease and iatrogenic exposure: a personal history of breast cancer, atypical ductal or lobular hyperplasia, LCIS, and previous chest-wall radiotherapy — classically mantle radiotherapy for Hodgkin lymphoma in adolescence. Dense breast tissue is both a risk factor and a mammographic confounder: it roughly doubles risk and hides small tumours, which is the rationale for MRI or tomosynthesis in dense breasts.[3]

[3]

Pathophysiology — the cascade and the three receptor stories

Carcinogenesis is a multistep pile-up of genetic hits, and the decisive hit is the one you treat. The classical morphological ladder is normal epithelium → usual hyperplasia → atypical hyperplasia → ductal carcinoma in situ → invasive ductal carcinoma — each rung a fresh escape from growth control, apoptosis, then the basement membrane.[3]

Three receptor stories, three different treatments. ER-positive tumours are driven by oestrogen through the oestrogen receptor, a ligand-activated transcription factor — starve them (aromatase inhibition, ovarian suppression) or block the receptor (tamoxifen). HER2-amplified tumours overexpress a receptor tyrosine kinase firing constitutive MAPK and PI3K signalling — aggressive, but uniquely sensitive to anti-HER2 antibodies and antibody-drug conjugates. Triple-negative tumours share only the absence of druggable receptors; many are basal-like and BRCA1-related, which is why platinum and PARP inhibitors work.[1]

The routes of spread explain the bedside signs. Direct extension tethers the lump to skin and chest wall. Lymphatic spread runs first to the axillary nodes, then to the supraclavicular and internal mammary chains; nodal burden is the dominant prognostic factor. Haematogenous spread seeds bone (about 70%, lytic or sclerotic), lung, liver and brain — and lobular carcinoma has a curious taste for the peritoneum and gastrointestinal serosa. Dermal lymphatic invasion by tumour emboli is the pathological signature of inflammatory breast cancer.[3]

The lump you cannot ignore — a painless hard mass is the test answer

About 70% of breast cancers present as a painless, hard, irregular, fixed lump — and the painlessness is the discriminator. Benign lumps are either smooth, mobile and painless (fibroadenoma) or tender and fluctuant (cyst, abscess). A hard, irregular, tethered lump in a woman over 40 is cancer until triple assessment proves otherwise.[3]

[3]

Characterise the lump at the bedside by site (quadrant and clock position), size, consistency, surface, edge and mobility — malignant lumps are hard, irregular, ill-defined, tethered, and do not transilluminate. Bilateral, multiple, soft, mobile, tender lumps favour a benign process.[3]

Nipple and skin changes carry the rest of the red flags. Recent unilateral nipple retraction in an older woman is tumour tethering the ducts. Significant nipple discharge is spontaneous, unilateral, single-duct, persistent, and bloodstained or serosanguineous — intraductal papilloma or carcinoma until excluded. Peau d'orange (oedematous skin pitted by hair follicles) is dermal lymphatic obstruction and the hallmark of inflammatory cancer. Eczematous erosion of the nipple-areola complex that will not settle is Paget disease.[3]

Atypical presentations are deliberately tested. Inflammatory cancer in a young woman is repeatedly misdiagnosed as mastitis — any "mastitis" not settling on antibiotics in two weeks, especially if she is not lactating, gets biopsied. Male breast cancer presents late with a retroareolar lump. Pregnancy-associated cancer hides in nodular lactating tissue. Occult cancer can present as axillary nodal metastases with an impalpable, mammographically occult primary found only on MRI.[3]

Differential — a lump is a finding, not a diagnosis

A breast lump is a finding, not a diagnosis; the triple assessment exists to separate benign from malignant. Three benign families dominate the differential, and the discriminator is always the same — hard, irregular, fixed, and over 35 means biopsy.[3]

[3]

The rule that prevents the lawsuit: any new, discrete, persistent lump in a woman over 35, or any lump with suspicious imaging, is sampled by core needle biopsy. No benign label is ever assigned on clinical grounds alone.[3]

Triple assessment — the 98% accurate spine

Three components, all three agreeing, 98% accurate — that single sentence is the most reproduced fact in breast surgery exams. Clinical examination plus imaging plus tissue sampling, done in one stop, is the cornerstone; any disagreement mandates excision biopsy or repeat sampling.[3]

1. Clinical examination — inspection and palpation of both breasts, regional nodes, and a focused systemic look.
2. Imaging — mammography and/or ultrasound, chosen by age and density; MRI in selected cases.
3. Tissue sampling — core needle biopsy (gold standard), fine-needle aspiration cytology, or excision biopsy.

[3]

Clinical breast examination is done with the patient sitting, exposed to the waist, inspected in four positions — arms by the side, hands pressed onto hips (to tense pectoralis), arms raised, and leaning forward — looking for asymmetry, contour change, skin and nipple changes, and visible masses. Palpation is supine, the ipsilateral arm raised above the head to spread the breast over the chest wall, palpating all four quadrants, the central areolar area, and the axillary tail of Spence with the flat of the fingers.[3]

[3]

Imaging by age. Mammography is first-line over 35; the malignant signs are clustered pleomorphic microcalcifications, a spiculated (star-like) mass, architectural distortion, and an asymmetric density persisting on spot compression. Findings are graded BI-RADS 0 to 6: 0 incomplete (recall), 1 negative, 2 benign, 3 probably benign (short-interval follow-up), 4 suspicious (biopsy), 5 highly suggestive of malignancy (biopsy), 6 biopsy-proven malignancy. Ultrasound is first-line under 35 and complementary at any age; MRI is reserved for high-risk screening, dense breasts, neoadjuvant response, the augmented breast, and the occult primary.[3]

Why core, not FNA. The 14-gauge core needle biopsy, taken under ultrasound or stereotactic guidance, is the gold standard because it preserves architecture and yields the four facts that decide systemic therapy — histology, grade, and ER, PR, HER2, Ki-67. Genomic assays (Oncotype DX, MammaPrint) on the core guide chemotherapy in ER-positive node-negative disease. FNA cannot assess invasion or receptors; it survives only for cyst aspiration and sampling a suspicious node.[1]

Staging and genetics. Confirmed invasive cancer is staged with CT chest/abdomen/pelvis, bone scan, and (selectively) FDG-PET/CT. BRCA genetic testing is offered for young age (under 45 to 50), triple-negative disease under 60, bilateral disease, male breast cancer, ovarian cancer in patient or family, or a strong family history — increasingly as multigene panel testing.[3]

Screening — inviting the well, not the symptomatic

Screening is a different question from triple assessment: it invites asymptomatic women on the basis of age or risk. The two organised programmes dominate the exam, and the numbers are the marks.[3]

The NHS Breast Screening Programme (NHSBSP) invites women aged 50 to 70 for two-view mammography every three years (extending to 47 to 73). Mammography finds microcalcifications and small masses years before they are palpable, shifting the stage mix toward DCIS and small node-negative cancers, and lowers breast-cancer mortality by about 20% in the invited population. The principal harm is overdiagnosis — indolent cancers that would never have surfaced clinically — alongside false-positive recalls and radiation exposure.[3]

High-risk women are screened differently. BRCA1/2 carriers and women with a lifetime risk above 20 to 25% are offered annual breast MRI from age 30 to 50, with annual mammography added from age 40; survivors of mantle radiotherapy for Hodgkin lymphoma between ages 10 and 30 start MRI-based screening 8 to 10 years after radiation. Chemoprevention with tamoxifen 20mg OD for 5 years (pre- or postmenopausal) or raloxifene (postmenopausal) lowers ER-positive incidence in high-risk women.[3]

The oncological emergencies — when breast cancer is a today problem

Breast cancer is not usually a surgical emergency — but four presentations are. Recognise them, treat them now, and only then return to the elective staging pathway.[3]

[3]

These aside, the priority is to stage the patient, fix the molecular subtype, present the case at the MDT, and plan definitive locoregional and systemic therapy.[3]

Definitive treatment — surgery, radiotherapy, systemic, in that order

Definitive treatment is multimodal and multidisciplinary — surgery, radiotherapy and systemic therapy combined differently for early, locally advanced and metastatic disease, with the molecular subtype dictating the systemic arm. The three pillars below are the spine of every management answer.[3]

Surgery of the breast — BCT equals mastectomy

Wide local excision plus whole-breast radiotherapy is breast-conserving therapy, and it is survival-equivalent to mastectomy. NSABP B-06, the Milan trial, and the EBCTCG meta-analysis established that BCT matches mastectomy provided margins are clear and radiotherapy is delivered — omitting radiotherapy after WLE roughly doubles local recurrence and raises breast-cancer mortality.[4]

Mastectomy is preferred when the tumour is large relative to the breast, multicentric, inflammatory, when WLE cannot clear margins, when radiotherapy is contraindicated (pregnancy, prior chest irradiation, severe connective tissue disease), or by patient choice. Skin-sparing and nipple-sparing techniques improve the cosmetic result when immediate or delayed reconstruction — implant, tissue expander, or autologous flap (DIEP, TRAM, latissimus dorsi) — is planned; reconstruction does not compromise oncological control when margins and radiotherapy are handled properly.[3]

Surgery of the axilla — sentinel first, not clearance

Axillary nodal status is the single most powerful prognostic factor, and the philosophy has shifted from routine clearance to a staged, less-invasive approach. Sentinel lymph node biopsy (SLNB) is the standard for the clinically and radiologically node-negative axilla: inject a blue dye (methylene blue or patent blue V) and/or a radioisotope (technetium-99-labelled colloid) at the tumour, areola or periareolar skin, then excise the first draining node(s).[3]

If the sentinel node is negative, no further axillary surgery is needed (NSABP B-32). If one to two nodes are positive and the patient is having breast-conserving therapy with whole-breast radiotherapy, completing axillary clearance adds no survival benefit in selected women (ACOSOG Z0011). Heavier nodal burden still receives axillary clearance or radiotherapy. Counsel about lymphoedema, seroma, shoulder stiffness and intercostobrachial sensory loss before the operation, not after.[3]

Radiotherapy — halves recurrence, lowers 15-year mortality, mind the heart

Whole-breast radiotherapy after WLE halves local recurrence and lowers 15-year breast-cancer mortality by about a sixth — roughly one death avoided for every four recurrences prevented. A tumour-bed boost is added for high-risk patients. Post-mastectomy radiotherapy is offered for tumours over 5cm, four or more positive nodes, T4 disease, or positive margins.[4]

The benefit is real, and so are the late risks. Older regimens measurably increased ischaemic heart disease (more after left-sided treatment) and second lung cancers, particularly in smokers; modern techniques — breath-hold, intensity-modulated radiotherapy, prone positioning — minimise cardiac and pulmonary dose, and smoking cessation substantially lowers the radiation-related lung-cancer risk. Net benefit favours radiotherapy for almost every non-smoker.[7]

Systemic therapy — adjuvant or neoadjuvant, subtype-decided

Systemic therapy is dictated by the molecular subtype, nodal status, tumour size, grade, Ki-67 and genomic score, and is given adjuvant (after surgery) or neoadjuvant (before). Four drug families map onto the subtypes below.[3]

Endocrine therapy by menopause status — the TAPI rule

Endocrine therapy goes to all ER-positive disease, and the agent is chosen by menopausal status. TAPI is the viva answer.[3]

[3]

In premenopausal women, tamoxifen 20mg orally once daily for 5 to 10 years is the standard — a SERM that antagonises oestrogen at the breast but is a partial agonist at the endometrium and on coagulation, producing its signature toxicities of venous thromboembolism (2 to 3x), endometrial cancer (2 to 3x), hot flushes and menstrual irregularity. In postmenopausal women, aromatase inhibitors — letrozole 2.5mg OD, anastrozole 1mg OD, or exemestane 25mg OD — are preferred (ATAC), trading VTE and endometrial risk for osteoporosis and arthralgia.[3]

The classic trap: prescribing an aromatase inhibitor to a premenopausal woman without ovarian suppression is futile — her ovaries make the oestrogen the drug cannot block. Add goserelin 3.6mg subcutaneously monthly (or 10.8mg 3-monthly) first, or use tamoxifen.[3]

HER2 — trastuzumab, pertuzumab, deruxtecan, and the echo machine

HER2-directed therapy transformed a once-lethal subtype into a treatable one — name the drugs, the doses, and the monitoring. Trastuzumab (Herceptin), a monoclonal antibody against the HER2 external domain, is given at 8mg/kg loading then 6mg/kg every 3 weeks for one year (HERA) with chemotherapy; pertuzumab (840mg loading then 420mg every 3 weeks) is added in higher-risk and neoadjuvant dual-blockade regimens.[5]

Trastuzumab's signature toxicity is cardiotoxicity — an asymptomatic drop in LVEF and occasionally heart failure, usually reversible on stopping — so echocardiographic monitoring before and during treatment is mandatory. In metastatic disease the armamentarium extends to the antibody-drug conjugate trastuzumab emtansine (T-DM1) and, for the newly defined HER2-low category (IHC 1+ or 2+ without amplification), trastuzumab deruxtecan, which nearly doubled overall survival versus chemotherapy in DESTINY-Breast04.[5]

Triple-negative — chemo, platinum, immunotherapy, PARP

Triple-negative breast cancer has no targetable receptor, so chemotherapy is the systemic backbone — but it is increasingly individualised by BRCA status and PD-L1. Neoadjuvant platinum (carboplatin) improves pathological complete response in basal-like disease, and pembrolizumab 200mg IV every 3 weeks, added to chemotherapy and continued adjuvantly, is now standard for PD-L1-positive early and metastatic triple-negative disease.[1]

The backbone regimen is the anthracycline-taxane sequence — doxorubicin 60mg/m2 plus cyclophosphamide 600mg/m2 every 3 weeks for four cycles (AC), then paclitaxel 175mg/m2 every 3 weeks or weekly 80mg/m2 for 12 weeks (AC-T); docetaxel plus cyclophosphamide (TC) is the alternative when anthracyclines are contraindicated. Anthracyclines carry dose-dependent cardiotoxicity (monitor LVEF); taxanes cause alopecia, neuropathy and neutropenia.[1]

For BRCA1/2-mutated HER2-negative metastatic disease, the PARP inhibitor olaparib 300mg orally twice daily improved progression-free survival in OlympiAD (7.0 versus 4.2 months; hazard ratio 0.58). Neoadjuvant therapy also downsizes large tumours for conservation, treats inflammatory cancer first, and reads in-vivo chemosensitivity — a pathological complete response predicts an excellent prognosis and guides escalation or de-escalation.[1][6]

Metastatic (Stage IV) — incurable but treatable, in years

Metastatic breast cancer is incurable but treatable, with median survival now measured in years for many subtypes. Bone metastases are managed with antiresorptive therapy — zoledronic acid 4mg IV monthly or denosumab 120mg subcutaneously every 4 weeks — plus palliative radiotherapy for painful deposits and orthopaedic fixation of impending fractures. ER-positive metastatic disease adds endocrine therapy plus a CDK4/6 inhibitor (palbociclib 125mg OD, ribociclib, or abemaciclib), roughly doubling progression-free survival.[3]

HER2-positive metastatic disease runs through trastuzumab plus pertuzumab, then T-DM1, then trastuzumab deruxtecan for HER2-low disease. Triple-negative metastatic disease is treated by chemotherapy, immunotherapy for PD-L1-positive disease, and olaparib for germline BRCA carriers.[5][6]

The subtypes that bite — inflammatory, Paget, phyllodes, DCIS, male

Inflammatory breast cancer (T4d). The most aggressive subtype, defined pathologically by dermal lymphatic invasion by tumour emboli. The breast is rapidly enlarged, warm, erythematous, indurated and tender, with peau d'orange and confluent change rather than a discrete lump — repeatedly misdiagnosed as mastitis or cellulitis. Treatment is primary systemic therapy (anthracycline-taxane chemo, anti-HER2 if HER2-positive), then mastectomy and axillary clearance, then chest-wall and nodal radiotherapy. Prognosis remains poor.[3]

Paget disease of the nipple. An eczematous, scaling, weeping, itchy erosion of the nipple-areola complex caused by intraepidermal spread of malignant Paget cells (large, clear, pale) from an underlying ductal carcinoma; 50 to 90% have associated DCIS or invasive cancer. Any unilateral nipple eczema not settling with topical treatment in two to three weeks is biopsied. Treatment is that of the underlying cancer.[3]

Phyllodes tumour. A fibroepithelial neoplasm of stromal origin, classified benign, borderline or malignant by stromal cellularity, mitoses, margins and overgrowth. It presents as a rapidly growing, large, smooth, well-circumscribed mass in women 40 to 50. Treatment is wide local excision with at least 1cm margins — and sentinel node biopsy is NOT indicated, because spread is haematogenous and nodal involvement is rare.[3]

Ductal carcinoma in situ (DCIS). Non-invasive, contained by the basement membrane, and therefore cannot metastasise — but untreated, 30 to 50% progress to invasive cancer. Usually found as microcalcifications on screening. Treatment is WLE plus whole-breast radiotherapy (mastectomy for large or multicentric disease), with tamoxifen for ER-positive DCIS. The axilla does not require staging in pure DCIS.[3]

Male breast cancer. About 1% of all breast cancer, presenting late with a unilateral retroareolar lump, nipple retraction, ulceration or discharge. Histology is nearly always ductal and ER-positive, so mastectomy (not WLE) is the surgical standard and tamoxifen 20mg OD is the endocrine therapy of choice even in men — ASCO confirms tamoxifen first-line, with a GnRH agonist plus aromatase inhibitor reserved for those who cannot tolerate it. All men with breast cancer should be offered genetic testing, as BRCA2 (and to a lesser extent BRCA1) carriage is high.[2]

Complications — the preventable-harm list

Complications track the treatment modality, and the ones examiners test are the preventable ones. Surgery brings seroma (the commonest, aspirated), haematoma, wound infection, lymphoedema (5 to 8% after SLNB, 25 to 40% after full axillary clearance), shoulder stiffness, chronic pain, and intercostobrachial sensory loss. Counselling and a compression sleeve come before the operation, not after.[3]

Radiotherapy brings acute skin erythema and desquamation, then late fibrosis, cardiac toxicity (ischaemic heart disease, worse after left-sided treatment), pneumonitis, brachial plexopathy, and a small excess of secondary angiosarcoma decades later. Modern planning and smoking cessation minimise the cardiac and lung burden.[7]

Systemic therapy brings chemotherapy-induced alopecia, nausea, neutropenia and sepsis, anthracycline and trastuzumab cardiotoxicity (the former dose-dependent and often permanent, the latter frequently reversible on stopping), taxane neuropathy, tamoxifen-related VTE and endometrial cancer, and aromatase-inhibitor osteoporosis and arthralgia.[1][3]

The classic pitfalls: treating inflammatory cancer as mastitis; assigning a benign diagnosis on clinical grounds alone; planning therapy without ER/PR/HER2; using tamoxifen in a postmenopausal woman without considering an AI; omitting genetic testing in a man or a young woman with triple-negative disease; missing a second primary in the contralateral breast; forgetting lymphoedema counselling.[3]

Staging and prognosis — TNM, nodal burden, subtype

Prognosis is driven by TNM stage, nodal burden, tumour grade and molecular subtype — in that order of weight. TNM-8 measures invasive size in millimetres, includes clinical and pathological nodal categories, and folds biological factors into prognostic staging groups rather than anatomy alone.[3]

The anatomical T categories: T1 up to 20mm (T1mi, T1a, T1b, T1c), T2 over 20 up to 50mm, T3 over 50mm, T4 extending to chest wall (T4a), skin (T4b), both (T4c), or inflammatory (T4d). N runs N0 to N3 (infraclavicular or supraclavicular); M0 and M1 denote absence or presence of distant metastasis.[3]

[3]

Subtype heavily modifies these figures. Luminal A is best; HER2-enriched was once worst but has been transformed by trastuzumab; triple-negative now carries the worst prognosis, with recurrence concentrated in the first three years and a taste for visceral and brain metastases. A pathological complete response to neoadjuvant chemotherapy — commonest in HER2-positive and triple-negative disease — confers an excellent prognosis and guides escalation (T-DM1 in HER2+, capecitabine in triple-negative) or de-escalation.[1]

Special populations — pregnancy, BRCA carriers, the frail

Pregnancy-associated breast cancer (diagnosed in pregnancy or the first postpartum year) is delayed by the nodular, dense lactating breast. Ultrasound is the imaging of choice (mammography is safe with abdominal shielding; gadolinium MRI is avoided in the first trimester); core biopsy is safe. Surgery is safe in any trimester; radiotherapy is deferred until after delivery; chemotherapy is safe in the second and third trimesters (anthracycline-based) but avoided in the first; tamoxifen is absolutely contraindicated (teratogenic).[3]

BRCA1/2 carriers carry 55 to 72% and 45 to 69% lifetime breast cancer risk respectively, and a markedly elevated ovarian cancer risk. Management combines enhanced surveillance (annual breast MRI from age 25, mammography from 30), chemoprevention, and risk-reducing surgery — bilateral risk-reducing mastectomy lowers breast cancer risk by about 90 to 95%, and bilateral salpingo-oophorectomy around age 35 to 40 (after childbearing) dramatically lowers ovarian cancer risk and, premenopausally, breast cancer risk too.[3]

The trials that changed practice

The modern management of breast cancer is one of the most evidence-rich areas of medicine, built on the landmark trials below and the serial meta-analyses of the Early Breast Cancer Trialists' Collaborative Group (EBCTCG). NSABP B-04 and B-06 established BCT equivalence to mastectomy; NSABP B-32 validated SLNB for node-negative disease; ACOSOG Z0011 spared selected women completion clearance; ATAC and SOFT/TEXT refined endocrine therapy; HERA fixed one year of trastuzumab as standard.[3]

[4] [7] [6] [5] [3] [3] [3]

The mantra, and the pearls

The mantra: Triple assessment first. Receptor status before the drugs. Always examine the other breast.[3][2]

[3]

Ward-round test — three stems, thirty seconds each

Stem 1 — the classic lump (answer)

A 52-year-old woman has a painless, hard, irregular 2.5cm mass in the right upper outer quadrant, with skin tethering. What is the pathway, and what must you not omit? Model: This is breast cancer until proven otherwise. Triple assessment at the one-stop clinic — clinical examination, mammography plus ultrasound (she is over 35), and core needle biopsy with ER, PR, HER2 and Ki-67 requested on the sample. Do not omit the receptors — they write the systemic plan. Then stage, present at the MDT, and offer breast-conserving therapy (WLE plus whole-breast radiotherapy, survival-equivalent to mastectomy) with sentinel lymph node biopsy for the clinically node-negative axilla. Systemic therapy follows the subtype.[3][4]

Stem 2 — the red breast that is not mastitis (answer)

A 38-year-old non-lactating woman has a warm, erythematous, enlarged breast with peau d'orange, not settling after a week of antibiotics. What is the diagnosis and the first treatment step? Model: This is inflammatory breast cancer (T4d) until proven otherwise — dermal lymphatic invasion is the pathology. Biopsy the skin and any underlying mass; do not book a primary mastectomy for an "infection". The correct sequence is primary systemic therapy first (anthracycline-taxane chemotherapy, with anti-HER2 therapy if HER2-positive), then mastectomy and axillary clearance, then chest-wall and nodular radiotherapy. Prognosis is poor; the only error bigger than missing it is treating it as mastitis.[3]

Stem 3 — the man with a retroareolar lump (answer)

A 68-year-old man has a unilateral, hard, retroareolar lump with nipple retraction. Core biopsy confirms invasive ductal carcinoma, ER-positive. What operation, what endocrine therapy, and what referral must you make? Model: The operation is mastectomy (not breast-conserving therapy) with staging of the axilla; the endocrine therapy is tamoxifen 20mg OD, which remains first-line even in men (ASCO), reserving a GnRH agonist plus aromatase inhibitor for those who cannot tolerate it. And — the step most often missed — offer genetic testing, because BRCA2 (and to a lesser extent BRCA1) carriage is high in male breast cancer.[2]

References

1. [1]Leon-Ferre RA, Goetz MP. Advances in systemic therapies for triple negative breast cancer BMJ, 2023.PMID 37253507
2. [2]Hassett MJ, Somerfield MR, Baker ER, et al. Management of Male Breast Cancer: ASCO Guideline J Clin Oncol, 2020.PMID 32058842
3. [3]Waks AG, Winer EP. Breast Cancer Treatment: A Review JAMA, 2019.PMID 30667505
4. [4]Darby S, McGale P, Correa C, et al. Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: meta-analysis of individual patient data for 10,801 women in 17 randomised trials Lancet, 2011.PMID 22019144
5. [5]Modi S, Jacot W, Yamashita T, et al. Trastuzumab Deruxtecan in Previously Treated HER2-Low Advanced Breast Cancer N Engl J Med, 2022.PMID 35665782
6. [6]Robson M, Im SA, Senkus E, et al. Olaparib for Metastatic Breast Cancer in Patients with a Germline BRCA Mutation N Engl J Med, 2017.PMID 28578601
7. [7]Taylor C, Correa C, Duane FK, et al. Estimating the Risks of Breast Cancer Radiotherapy: Evidence From Modern Radiation Doses to the Lungs and Heart and From Previous Randomized Trials J Clin Oncol, 2017.PMID 28319436