Quick Answer
Breast diseases account for 2–3 NEET PG questions per paper across Surgery and Oncology. The high-yield framework:
- Triple assessment — clinical, imaging, core biopsy (FNAC obsolete).
- Benign disease — fibroadenoma (young, mobile, "breast mouse"), fibrocystic changes, phyllodes, mastitis, duct ectasia.
- Cancer subtypes — Luminal A/B (ER+), HER2+, triple-negative; molecular subtype drives therapy.
- Screening — USPSTF 2024 biennial mammography 40–74; India: CBE every 5 years 30–65 (ICMR).
- Surgery — BCS = MRM in survival when margins clear and radiotherapy given (NSABP B-06).
- SLNB before ALND in clinically node-negative; Z0011 spares ALND in ≤2 positive SNs.
- Adjuvant therapy — endocrine for ER+, trastuzumab for HER2+, chemotherapy for triple-negative or high-risk.
- Inflammatory breast cancer — T4d; neoadjuvant chemo first, then mastectomy + radiotherapy.
Breast cancer is the most common cancer in Indian women (40 per 100,000) and a near-certain NEET PG topic. The pattern of questions has shifted from anatomy and historical surgical eponyms toward modern oncology — molecular subtypes, neoadjuvant therapy, sentinel node biology, and screening guideline specifics. This NEETPGAI deep dive consolidates everything from benign breast disease through metastatic cancer therapy into the highest-yield concepts that NEET PG 2026 examiners are likely to test.
Pair this guide with practice on the Surgery subject hub and the oncology fundamentals article for a robust surgical-oncology base. Examiners frequently link breast cancer to genetics (BRCA), endocrinology (tamoxifen, AIs), and OBG (pregnancy-associated breast cancer) — multi-disciplinary mastery is essential.
Benign breast disease — the differentials
Fibroadenoma
The most common benign breast tumour in women aged 15–35. Painless, well-circumscribed, mobile lump (the classic "breast mouse"). USG: well-defined hypoechoic mass with parallel orientation.
- Triple assessment still mandatory.
- Management: observation if <3 cm and triple assessment benign (BIRADS 3). Excise if >3 cm, growing, or patient anxiety.
- Giant fibroadenoma (>5 cm) — adolescents, surgical excision.
- Juvenile fibroadenoma — distinct entity, pubertal girls, rapid growth, excision preferred.
Fibrocystic changes
The most common benign breast condition, peaking ages 30–50. Cyclical pain (mastalgia) and lumpiness, worse premenstrually. Imaging shows multiple cysts of varying sizes.
- Aspiration of palpable cyst: if straw-coloured fluid and the lump disappears, no further workup. If bloody fluid, residual mass, or recurrence, send for cytology and image.
- Atypical hyperplasia (ductal/lobular) — relative risk of cancer is ~4×; counselling and chemoprevention with tamoxifen may be considered.
Phyllodes tumour
Stromal tumour with leaf-like architecture; classified as benign, borderline, or malignant. Rapid growth in middle-aged women. Wide local excision with 1 cm margins; mastectomy if large. Axillary dissection NOT routinely required (rarely metastasises to nodes).
Mastitis and breast abscess
- Lactational mastitis — Staphylococcus aureus most common. Continue breastfeeding, oral flucloxacillin/dicloxacillin, ultrasound-guided aspiration if abscess (preferred over incision and drainage).
- Non-lactational (periductal mastitis) — mixed flora; smoking is the leading risk factor; can produce mammary duct fistula.
Duct ectasia and intraductal papilloma
- Duct ectasia: dilated subareolar ducts, green-brown nipple discharge, slit-like nipple retraction.
- Intraductal papilloma: most common cause of bloody nipple discharge, single duct involved. Microdochectomy is curative.
Breast cancer — biology and risk factors
Risk factors
- Genetic: BRCA1 (chromosome 17q21) and BRCA2 (13q12) — autosomal dominant, lifetime breast cancer risk 60–70% (BRCA1) and 45–55% (BRCA2). BRCA1 also increases triple-negative and ovarian cancer risk; BRCA2 increases male breast and pancreatic cancer.
- Hormonal: early menarche (<12), late menopause (>55), nulliparity, first child after 30, HRT >5 years, OCP marginal.
- Family history: first-degree relative doubles risk; doubles again if <50 at diagnosis.
- Lifestyle: alcohol, obesity post-menopause, sedentary lifestyle.
- Radiation: prior chest radiotherapy (e.g., for Hodgkin lymphoma in childhood) — major risk.
- Atypical hyperplasia, LCIS, dense breasts.
Histological types
| Type | Features |
|---|
| Invasive ductal carcinoma (IDC), NST | 70–80%; firm, irregular, stellate on mammogram |
| Invasive lobular carcinoma (ILC) | 5–10%; "Indian-file" pattern, often bilateral, harder to detect on mammogram |
| DCIS | Premalignant, microcalcifications on mammogram, no nodal spread; treated as in-situ |
| LCIS | Risk marker rather than precursor; bilateral risk; tamoxifen chemoprevention |
| Medullary | Younger patients, BRCA1, lymphocytic infiltrate, better prognosis |
| Mucinous (colloid) | Older women, indolent, good prognosis |
| Tubular | Small, well-differentiated, excellent prognosis |
| Inflammatory breast cancer (T4d) | Erythema, peau d'orange, dermal lymphatic invasion; aggressive |
Molecular (intrinsic) subtypes
| Subtype | ER | PR | HER2 | Ki-67 | Treatment cornerstone |
|---|
| Luminal A | + | + | − | Low | Endocrine therapy |
| Luminal B (HER2−) | + | ± | − | High | Endocrine + chemo |
| Luminal B (HER2+) | + | ± | + | Any | Endocrine + chemo + anti-HER2 |
| HER2-enriched | − | − | + | High | Chemo + anti-HER2 |
| Triple-negative (basal) | − | − | − | High | Chemo ± immunotherapy ± PARP-i |
Screening — guidelines and modalities
USPSTF 2024 (US guideline)
- Biennial mammography for average-risk women aged 40–74 years.
- Insufficient evidence above 75.
ACS
- Annual mammography 45–54.
- Biennial 55+.
- Optional from 40 if patient prefers.
India (ICMR / National Cancer Grid)
- No nationwide screening programme owing to resource constraints.
- Clinical breast examination (CBE) every 5 years for women aged 30–65 is recommended at primary care level.
- Mammography reserved for symptomatic women, high family-history risk, or BIRADS 4/5 lesions.
Modalities
- Mammography — gold standard for screening. Sensitivity 70–80%; lower in dense breasts. Suspicious findings: clustered microcalcifications, spiculated mass, architectural distortion. BIRADS 4–5 require biopsy.
- Digital breast tomosynthesis (3D) — improves detection in dense breasts.
- Ultrasound — first-line in women under 35 and pregnant; differentiates cysts from solid masses.
- MRI — annual screening for high-risk groups (BRCA carriers, prior chest radiotherapy, lifetime risk >20%).
Diagnostic workup — triple assessment
Mandatory for any breast lump:
- Clinical examination — size, mobility, skin changes, nipple, axillary nodes.
- Imaging — mammography (over 35) ± USG (under 35).
- Tissue diagnosis — core needle biopsy is now standard (replaces FNAC because core distinguishes invasive from in-situ disease and provides ER/PR/HER2 receptor status).
Concordance across all three rules out cancer; any discordance triggers excision biopsy.
Staging — AJCC 8th edition (anatomic + biologic)
The 8th edition incorporates ER/PR/HER2 status and grade into prognostic staging — a notable shift from purely anatomic staging.
- T1 ≤2 cm; T2 2–5 cm; T3 >5 cm; T4 chest wall (T4a), skin (T4b), both (T4c), inflammatory (T4d).
- N1 mobile axillary; N2 fixed; N3 supraclavicular or internal mammary.
- M1 distant (bone > lung > liver > brain).
Staging workup for >T2 or any node-positive: chest imaging, abdominal USG/CT, bone scan or PET-CT for advanced disease.
Surgery — BCS vs mastectomy
Breast-conserving surgery (BCS) — equivalent survival to mastectomy
NSABP B-06 and Milan trials showed equivalent long-term survival between BCS + radiotherapy and mastectomy for early-stage disease.
- Lumpectomy/wide local excision with negative margins (no ink on tumour).
- Whole-breast radiotherapy is integral; otherwise, recurrence rates are unacceptable.
Contraindications to BCS
- Multicentric disease (separate quadrants).
- Diffuse suspicious microcalcifications.
- Prior chest wall radiotherapy.
- Persistent positive margins after re-excision.
- Large tumour relative to breast (poor cosmetic outcome).
- Pregnancy first/second trimester (radiation contraindication).
- Inflammatory breast cancer.
- Some BRCA carriers prefer bilateral mastectomy.
Modified radical mastectomy (MRM)
Removes breast and level I–II axillary nodes while preserving pectoralis muscles. Now largely replaced by SLNB-guided dissection when nodes are clinically negative. Halsted's classical radical mastectomy is historical — too morbid.
Axillary management
- Sentinel lymph node biopsy (SLNB) — first-line in clinically node-negative early breast cancer using blue dye and/or technetium-99m sulphur colloid. The first node to take up the dye is sampled.
- ACOSOG Z0011 trial: in T1–T2 with ≤2 positive sentinel nodes undergoing BCS + whole-breast radiation, completion axillary clearance can be omitted without survival detriment.
- Axillary lymph node dissection (ALND, levels I–III) still indicated for N2/N3 disease, gross axillary involvement, and inflammatory breast cancer.
Reconstruction
- Immediate (at mastectomy) or delayed.
- Implant-based or autologous (DIEP flap, TRAM flap, latissimus dorsi).
- Discuss with patient before mastectomy is finalised.
Adjuvant systemic therapy
Endocrine therapy (ER+ disease)
- Premenopausal: tamoxifen (selective ER modulator) for 5–10 years; consider ovarian suppression (GnRH agonist) plus aromatase inhibitor in high-risk.
- Postmenopausal: aromatase inhibitor (letrozole, anastrozole, exemestane) for 5–10 years.
- Tamoxifen risks: endometrial cancer, VTE, hot flushes. AI risks: osteoporosis, arthralgia, no endometrial risk.
Anti-HER2 therapy
- Trastuzumab (humanised monoclonal antibody) for 12 months; reduces recurrence by ~50%.
- Pertuzumab added to trastuzumab in node-positive HER2+.
- T-DM1 (trastuzumab emtansine) for residual disease after neoadjuvant therapy.
- Cardiotoxicity: monitor LVEF every 3 months; usually reversible (unlike anthracyclines).
Chemotherapy
- Triple-negative or high-risk node-positive: anthracycline + taxane (AC-T regimen).
- Triple-negative: pembrolizumab (immune checkpoint inhibitor) added in stage II–III; PARP inhibitors (olaparib) for BRCA-mutated TNBC.
- Neoadjuvant chemotherapy is standard for inflammatory, locally advanced, and most triple-negative or HER2+ disease — downsizes tumour, allows BCS, enables pathological response assessment (pCR strongly predicts outcomes).
Radiotherapy
- After all BCS.
- After mastectomy if T3/T4, ≥4 positive nodes, positive margins, or inflammatory disease.
Special situations
Inflammatory breast cancer (T4d)
Aggressive subtype with peau d'orange, erythema, warmth, and dermal lymphatic invasion. Always neoadjuvant chemotherapy first, followed by mastectomy and radiotherapy. BCS contraindicated.
Pregnancy-associated breast cancer
Mastectomy and chemotherapy possible after first trimester (anthracyclines and taxanes safe in second/third). Radiotherapy and tamoxifen contraindicated during pregnancy. SLNB with technetium is usually safe; blue dye contraindicated.
Male breast cancer
<1% of breast cancer; almost always ER+. BRCA2 association strong. Mastectomy + endocrine therapy is standard. Often presents late with poorer prognosis.
Paget disease of nipple
Eczematous nipple change with underlying DCIS or invasive carcinoma. Punch biopsy of nipple skin shows Paget cells (large, vacuolated). Mastectomy or BCS with central duct excision + radiotherapy.
High-yield NEET PG MCQ traps
- FNAC vs core biopsy — core biopsy now preferred; FNAC cannot distinguish in-situ from invasive.
- Most common benign breast tumour — fibroadenoma; "breast mouse".
- Most common malignancy in Indian women — breast cancer (overtook cervical cancer ~2010).
- Z0011 trial — omit ALND with ≤2 positive sentinel nodes if BCS + WBRT.
- BRCA1 vs BRCA2 — BRCA1 chromosome 17, triple-negative tendency, ovarian; BRCA2 chromosome 13, male breast, pancreatic.
- Inflammatory breast cancer treatment order — chemo first, then surgery, then radiotherapy.
- Tamoxifen risks — endometrial cancer, VTE, hot flashes.
- Trastuzumab toxicity — reversible cardiotoxicity (LVEF drop), unlike anthracyclines.
- Phyllodes management — wide local excision, NO axillary dissection (rare nodal mets).
- Bloody nipple discharge — most common benign cause is intraductal papilloma; rule out cancer.
Recent updates and Indian context
- USPSTF 2024: lowered screening start age to 40 (previously 50); biennial.
- ASCO/CAP 2023: HER2-low (IHC 1+ or 2+/FISH-negative) is now actionable with trastuzumab deruxtecan in metastatic disease.
- KEYNOTE-522 (2022 update): pembrolizumab + chemo standard in early high-risk triple-negative.
- OlympiA trial (2021): olaparib (PARP-i) for BRCA1/2 germline-mutated high-risk early breast cancer.
- Indian context: NCG-India 2024 guidance pragmatically endorses CBE-based screening over mammography due to cost; ICMR-funded TMC trials drive Indian-specific evidence base. Late-stage presentation remains a major issue (≥50% present at stage III/IV).
Frequently asked questions
When should mammography screening begin in average-risk women?
USPSTF 2024 recommends biennial mammography from age 40 to 74 in average-risk women. ACS suggests annual from 45 to 54, then biennial. India has no nationwide screening programme, but ICMR recommends clinical breast examination for women 30 to 65 every 5 years; mammography is reserved for symptomatic women or those with family history.
What does the triple assessment include?
Triple assessment is the gold standard for any breast lump: (1) clinical examination, (2) imaging — mammography in women over 35 or USG in younger women, and (3) tissue diagnosis by core biopsy (FNAC has fallen out of favour because it cannot distinguish in-situ from invasive disease). Concordance among all three confirms diagnosis.
When is breast-conserving surgery contraindicated?
BCS is contraindicated in: multicentric disease (separate quadrants), diffuse microcalcifications, prior chest wall radiotherapy, persistent positive margins after re-excision, large tumour relative to breast size with poor cosmetic outcome, pregnancy in first or second trimester (radiotherapy harm), and inflammatory breast cancer. Genetic mutations like BRCA are relative — bilateral mastectomy may be preferred.
What is sentinel lymph node biopsy?
SLNB identifies the first node draining the tumour using blue dye and/or radiocolloid (technetium-99m sulphur colloid). It replaces axillary clearance in clinically node-negative breast cancer, sparing the morbidity of lymphedema and shoulder dysfunction. ACOSOG Z0011 showed completion ALND can be omitted with up to 2 positive sentinel nodes treated with whole-breast radiation.
Which patients need adjuvant trastuzumab?
HER2-positive breast cancer (IHC 3+ or FISH-amplified) requires 1 year of trastuzumab in combination with chemotherapy. Adding pertuzumab is recommended in node-positive HER2+ disease. Cardiotoxicity (LVEF reduction) is monitored every 3 months — usually reversible. Trastuzumab transformed HER2+ breast cancer from worst to one of the better prognosis subtypes.
This content is for educational purposes for NEET PG exam preparation. It is not a substitute for professional medical advice, diagnosis, or treatment. Clinical information has been reviewed by qualified medical professionals.
Written by: NEETPGAI Editorial Team
Reviewed by: Pending SME Review
Last reviewed: April 2026
