🩺 Malignant breast disease is a spectrum from in situ (pre-invasive) to invasive cancer. 🎯 Exam focus: recognise red flags 🚩, use triple assessment (clinical + imaging + biopsy), and link treatment to stage and ER/PR/HER2 status.

🔑 Key Definitions (high-yield)

🧱 In situ: malignant cells are contained within the basement membrane (non-invasive).
🧨 Invasive: malignant cells have breached the basement membrane → access to lymphatics/blood → metastasis risk.
🧬 Receptor status: ER, PR, HER2 guide prognosis + systemic therapy choices.

🧠 Pathophysiology (why the “red flags” happen)

🧷 Skin dimpling/tethering: tumour fibrosis pulls on Cooper’s ligaments.
🍊 Peau d’orange: dermal lymphatic obstruction → oedema and thickened “orange peel” skin.
🧲 Fixed/craggy mass: invasion into surrounding stroma and fascia.
🩸 Bloody nipple discharge: ductal involvement (benign papilloma can also do this, but malignancy must be excluded).

🚩 Presentation & Red Flags (OSCE wording)

Feature	Why it matters	What you say/do
🧱 Hard, irregular, immobile lump	Suggests invasion + fibrosis	Urgent breast clinic referral (two-week pathway if suspicious)
🧷 Skin tethering/dimpling	Ligament involvement	Document location (clock-face + cm from nipple), refer urgently
🧲 New nipple inversion/retraction	Ductal involvement/fibrosis	Urgent referral, include onset + laterality
🩸 Unilateral bloody discharge	Malignancy vs papilloma	Urgent referral (especially age >50 or associated lump)
🍊 Rapid diffuse redness/swelling, peau d’orange	Inflammatory breast cancer mimic of mastitis	Urgent same-day/senior discussion + breast clinic
🧿 Axillary lump	Nodal disease can present first	Urgent breast clinic + targeted axillary USS + sampling

🧪 Types of Malignant Breast Disease (exam table)

Diagnosis	Definition	Typical clues (“buzzwords”)	Key investigations	Core management
🟦 DCIS (Ductal Carcinoma In Situ)	Malignant ductal cells within basement membrane	Often screen-detected; may be asymptomatic	Mammogram: microcalcifications Biopsy: histology confirms DCIS + grade	Wire-guided wide local excision (often non-palpable) ± radiotherapy based on MDT risk
🟪 LCIS (Lobular Carcinoma In Situ)	Abnormal lobular cells; usually a risk marker for invasive cancer rather than an obligate precursor	Usually incidental on biopsy; often multifocal	Often biopsy finding Consider MRI/surveillance in high-risk pathways (MDT/genetics)	Risk counselling + surveillance; pleomorphic LCIS → treat more like DCIS (excision)
🟥 Invasive ductal carcinoma (NST) (~80%)	Invasive malignancy arising from ductal epithelium	Hard, craggy, fixed lump; skin/nipple changes; nodes	USS: suspicious solid lesion, may be incompressible Mammogram: mass, asymmetry, spiculated distortion, ± calcifications Core biopsy: type/grade + ER/PR/HER2	Surgery (WLE or mastectomy) + axillary staging + adjuvant systemic therapy/radiotherapy per stage/biology
🟧 Invasive lobular carcinoma (~10%)	Invasive malignancy from lobules; often infiltrative pattern	Can be subtle: thickening/distortion rather than discrete lump; more multifocal/bilateral tendency	Imaging may be discordant → MRI helpful for extent Core biopsy for confirmation + receptors	As per invasive disease, but MDT often uses MRI for surgical planning
🟫 Paget’s disease of the nipple	Epidermal involvement by underlying ductal carcinoma	Itchy, red, eczematous/ulcerated nipple ± bloody discharge	Mammogram ± USS (look for DCIS/invasive cancer) Nipple biopsy confirms	Central excision or mastectomy depending on extent + treat underlying cancer (MDT)

🔎 The “Triple Assessment” (must say this in exams)

✅ Triple assessment = Clinical + Imaging + Tissue diagnosis. If these are discordant, you escalate (repeat imaging/biopsy, MDT, consider MRI).

Component	What you do	Concerning features
🩺 Clinical exam (P score)	Inspect + palpate both breasts + axillae/supraclavicular nodes	Fixed mass, skin tethering, peau d’orange, hard nodes
🖼️ Imaging (U/M)	Ultrasound (younger/dense breasts) ± mammogram (calcifications, architecture)	Spiculation, distortion, suspicious mass, abnormal nodes, microcalcifications
🧫 Biopsy (B/C)	Core biopsy of lesion; FNA/core of suspicious node	Histology confirms malignancy + grade + ER/PR/HER2

🧭 Staging & “extra tests” (what triggers them)

📏 TNM staging is foundational: tumour size, node involvement, metastases.
🧪 Baseline histology includes grade, lymphovascular invasion, and receptor status (ER/PR/HER2) ± Ki-67.
🖥️ CT staging is usually for higher-risk disease (e.g., heavy nodal burden / aggressive biology / symptoms) as directed by MDT.
🧲 Breast MRI: helpful for lobular cancer, dense breasts, multifocal disease suspicion, or discordant imaging.
🧬 Genetics: consider with strong family history, young onset, bilateral disease, male breast cancer, or triple-negative at younger ages (local genetics criteria apply).

🛠️ Management Overview (MDT-driven, exam-friendly)

⚖️ Treatment is chosen by the MDT based on stage + grade + ER/PR/HER2 + patient fitness/preferences. Most patients have surgery + tailored adjuvant therapy (or neoadjuvant therapy in selected cases).

🔪 Surgery + Axilla

✂️ Wide local excision (lumpectomy) or 🧱 mastectomy (choice depends on tumour size/extent, multifocality, patient preference).
🧭 Sentinel lymph node biopsy: identifies first draining nodes (typically tracer + dye) → staging with less morbidity than full clearance.
🦾 Axillary node dissection may be needed if significant nodal disease (balanced against lymphoedema risk).
🧩 Reconstruction: immediate or delayed options should be discussed (where appropriate).

💊 Systemic & Adjuvant Therapy (link to receptors)

Biology	Typical systemic approach	Key exam phrases
🌸 ER+ / PR+	Endocrine therapy: tamoxifen (often premenopausal) or aromatase inhibitor (often postmenopausal), typically 5–10 years	“Reduces recurrence by blocking oestrogen signalling”
🧲 HER2+	Trastuzumab (Herceptin) ± chemotherapy (regimens depend on stage/MDT)	“Monitor cardiac function (echo) due to cardiotoxicity risk”
⚫ Triple negative	Often chemotherapy-based; MDT may consider immunotherapy in selected settings; consider genetics where appropriate	“Aggressive biology; receptor-negative so endocrine/HER2 therapy won’t help”

☢️ Radiotherapy (core rules)

✅ After wide local excision, radiotherapy is usually recommended to reduce local recurrence.
🧱 After mastectomy, radiotherapy depends on risk (tumour size, margins, nodes) - not always required.

⚠️ Side Effects of Key Treatments (keep this table for exams)

Treatment	Important side effects	OSCE counselling line
🦾 Lymph node dissection	Unilateral lymphoedema, numbness, shoulder stiffness	“We’ll give physio advice and lymphoedema prevention guidance.”
🌸 Tamoxifen	Thrombosis risk, menopausal symptoms; small ↑ endometrial cancer risk	“Seek help for calf swelling/SOB; report abnormal bleeding.”
🍂 Aromatase inhibitors (anastrozole/letrozole/exemestane)	Arthralgia, menopausal symptoms, bone loss	“We monitor bone health and may add bone-protective therapy.”
🧲 Trastuzumab (Herceptin)	Cardiac toxicity, breathlessness, nausea/vomiting, neutropenia (esp. with chemo)	“We do baseline and interval echoes.”

📈 Prognosis (Nottingham Prognostic Index – NPI)

🧮 NPI combines tumour size, nodal status, and grade to estimate prognosis. NPI = (size in cm × 0.2) + nodal status + grade

Nodal status score	Nodes involved
1	0 nodes
2	1–4 nodes
3	>4 nodes

🩻 Screening (UK)

📨 Most UK programmes invite people registered as female for mammography every 3 years within a defined age range (local policy applies).
🧬 Higher-risk pathways (strong family history/BRCA) may involve earlier and more intensive surveillance (genetics/familial breast clinic).

🧠 One-line Round-Up (rapid recall)

Condition/Concept	One-liner
🟦 DCIS	Screen-detected microcalcifications; in situ ductal malignancy
🟪 LCIS	Incidental lobular lesion; risk marker (pleomorphic → treat like DCIS)
🟥 Invasive cancer	Hard, irregular, fixed mass ± skin/nipple change
🌸 ER+	Tamoxifen / aromatase inhibitor
🧲 HER2+	Trastuzumab (Herceptin) + monitor heart
⚫ Triple negative	Chemo-driven; consider genetics in the right patient
🟫 Paget’s	Eczematous nipple change = biopsy and look for underlying cancer
✅ Triple assessment	Clinical + imaging + biopsy (discordance → escalate)

🎯 OSCE Mini-Script (60–90 seconds)

👋 “I’ll start with symptoms (lump, pain, discharge), duration, change with cycle, systemic symptoms, and red flags (skin/nipple change).”
🧬 “I’ll ask risk factors: age, family history/BRCA, prior chest irradiation, HRT/menarche/menopause, alcohol, obesity.”
🩺 “On exam I’ll inspect then palpate all quadrants + axillae/supraclavicular nodes, and document clock-face position and size.”
✅ “Any suspicious finding needs urgent breast clinic referral for triple assessment.”

📚 References (UK MLA core)

NICE: Early and locally advanced breast cancer (NG101): https://www.nice.org.uk/guidance/ng101
NICE: Suspected cancer recognition and referral (NG12): https://www.nice.org.uk/guidance/ng12
NHS breast screening information: https://www.nhs.uk/conditions/breast-screening-mammogram/

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Malignant Breast Disease