Breast: Pathology Flashcards
What is tissues are present in the breast?
- Epithelial ducts and lobules (glandular tissue)
- Mesnchymal fat and fibrous tissue
What doe physiological changes of breast occur with?
Age and pregnancy
What is breast structure dependent on?
Hormones: oestrogen and progesterone
What is the structure of the breast?
- Each breast has 8 to 10 sections (lobes) arranged like the petals of a daisy
- Inside each lobe are many smaller structures called lobules
- At the end of each lobule are tiny sacs (bulbs) that can produce milk
How do breasts develop during puberty?
- Before puberty breasts in both sexes contain ducts
- There is variable degrees of branching but lack of lobules
- 15-25 lactiferous ducts
- Branching starts at the nipple and extends to the terminal ductal lobular unit
- Hormonally responsive
What do the lymph ducts of the breasts do?
Drain fluid that carries white blood cells from the breast tissues into lymph nodes in the axilla and behind the sternum
What do the lymph nodes of the breast do?
Filter harmful bacteria and play a key role in fighting off infection
Give examples of benign breast conditions.
- Fibrocystic change
- Fibroadenoma
- Intraduct papilloma
- Fat necrosis
- Duct ectasia
What is fibrocystic change?
- Fibrosis
- Adenosis
- Cysts
- Apocrine metaplasia
- Ductal epithelial hyperplasia (usual type, atypical)
What is a fibroadenoma?
Circumscribed mobile nodule in reproductive age
How does duct ectasia present?
Nipple discharge
How does fat necrosis occur?
Trauma
How does intraduct papilloma present?
- Lactiferous ducts
- Nipple discharge
What is the most common breast tumour in adolescent and young adult women?
Fibroadenoma (peak age= 3rd decade)
What can happen to firboadenomas if left untreated?
Can regress with age
How do fibroadenomas present?
- Well-circumscribed
- Freely mobile
- Nonpainful mass
What is the pathology behind fibroadenomas?
Proliferation of epithelial and stromal elements
What are the 2 types of growth pattern of fibroadenomas?
Intracanalicular pattern
- Ducts distorted elongated
- Slit-like structures
Pericanalicular pattern
-Ducts not compressed
How do tubular adenomas present?
- Less common than fibroadenomas
- Young women
- Discrete, freely movable mass
- Uniform sized ducts
How do lactating adenomas present?
- Enlarging mass during lactation or pregnancy
- Prominent secretory change
Who is usually affected by intraduct papillomas?
Middle aged women
What histological features may be present in intraduct papillomas?
Epithelial hyperplasia (may be atypical)
How do intraduct papillomas present?
Nipple discharge
What may there be history of with fat necrosis?
Antecedent trauma or prior surgical intervention
What can be seen on mammography of fat necrosis?
Fibrosis, calcifications and egg shell
What can fat necrosis simulate clinically and mammographically?
Carcinoma
What can be see on histology of fat necrosis?
- Histiocytes with foamy cytoplasm
- Lipid-filled cysts
What percentage of breast tumours are made up by phyllodes tumours?
<1%
What are phyllodes tumours?
- Fleshy tumours with leaf like pattern and cysts on cut surface
- They are circumscribed, connective tissue and epithelial ranged from 1-15cm
- Most benign, small proportion malignant
What type of metastasis is associated with phyllodes tumours?
Haematogenous
What is the epidemiology of breast carcinoma?
- Affects one in 8 females
- 22% of all female cancers
- 1 in 870 men
- Commonest cause of female cancer death (1/3 of affected women will die from disease)
- 350 males yearly in the UK
- 470,000 deaths worlwide
How do breast carcinomas present on mammography?
Soft tissue opacity with calcification
What is the macroscopic presentation of breast carcinomas?
- Hard lump
- Fixed mass
- Tethering to the skin
- Peau d’orange dimpling of skin
What are the risk factors for breast carcinoma?
- Gender
- Age
- Menstrual history
- Age at first pregnancy
- Radiation
- Family history
- Personal history
- Hormonal treatment
- Genetic factors
- Other factors: obesity, lack of physical activity, alcohol
Give examples of breast lesions and their relative risk of cancer.
Epithelial proliferation without atypia
RR 1.5-2x
Epithelial proliferation with atypia ductal or lobular
RR 4-5x
Lobular carcinoma in situ
RR 8-10x
Ductal carcinoma in situ
RR 8-10x
What percentage of breast cancer is attributable to inherited factors?
5-10%
What genes confer susceptibility to breast cancer?
- BRCA1 (20-40%)
- BRCA2 (10-30%)
- TP53 (<1%)
- PTEN (<1%)
- Other genes (30-70%)
How can breast cancers be classified histologically?
Non invasive
- DCIS
- LCIS
Invasive
- Invasive ductal carcinoma NST (~75%)
- Invasive lobular carcinoma and its variants (5-15%)
- Special types (all the rest)
What are the features of an in situ carcinoma?
- Preinvasive, does not form a palpable tumour
- Not detected clinically, only x-ray in DCIS screening
- Multicentricity and bilaterality (LCIS)
- No metastatic spread
- Risk of invasion depending on grade
What is the risk of progression with in situ cancer?
- Low grade DCIS: 30% in 15 years
- High grade DCIS: 50% in 8 years
- LCIS : 19% in 25 years and bilaterality
Give examples of breast cancer of special types
- Tubular carcinoma
- Mucinous carcinoma
- Carcinoma with medullary features
- Metaplastic carcinoma
- Other
What investigations are carried out for breast cancer?
- Clinical examination
- Radiology (Mammogram, ultrasound, MRI)
- Fine needle aspiration cytology FNA
- Needle core biopsy
- Wide local excision with adequate margin
What is the breast screening programme?
- Women aged 50-70 years are invited for mammogram every 3 years
- Lead to 30% reduction in mortality
What are microcalcifications?
- Tiny deposits of calcium which can appear anywhere in the breast and often show up on mammogram?
- Majority are harmless
- Some may be precancerous or cancerous
Who has microcalcifications?
Most women have 1 or more of various size
What are the 2 most important mammographic indicators of breast cancer?
- Masses
- Microcalcifications
What is included in the histology report of a breast tumour?
- Invasive vs. Non-invasive
- Histological Type-Ductal (85%) vs. Lobular
- Grade (estimate of the aggressiveness under microscope) .
- Size .
- Margins .
- Lymph Nodes .
- Oestrogen/ Progesterone Receptor (2/3 positive) .
- HER-2/ neu
Where can breast cancer spread locally?
- Skin
- Pectoral muscles
Where can breast cancer spread lymphatically?
Axillary and internal mammary nodes
Where can breast cancer spread haematogenously?
- Bone
- Lungs
- Liver
- Brain
What is prognosis of breast cancer dependent on?
- Node status (best prognostic indicator)
- Tumour size ( < 2cm )
- Type
- Grade (1,2,3 )
- Age
- Lymphovascular space invasion
- Hormone receptors
- HER2 status
- Proliferative rate
- Gene expression profile
What is the Nottingham prognostic index based on?
- Tumour size
- Grade
- Nodal status
What molecular markers are looked at in breast cancer for targeting treatments?
- ER /PR strong predictors of response to hormonal therapies
- ER/PR negative tumours do not respond
- HER-2 : about 20-30% positive- predicts response to trastuzumab ( Herceptin
What are the 5 molecular subtypes of breast cancer?
- Basal like
- Her 2+
- Normal
- Luminal A
- Luminal B
What are the features of luminal A breast cancer?
- ER-positive
- HER2-negative
- Low Ki67
What are the features of luminal B breast cancer?
- ER-positive
- HER2-positive (or HER2-negative with high Ki67)
What are the features of basal-like breast cancer?
- ER negative
- PR negative
- HER2 negative
What are the features of HER2 type breast cancer?
- ER negative
- PR negative
- HER2 positive
How is breast cancer managed?
- Staging
- Surgery (mastectomy, breast conserving surgery – WLE) + lymph nodes
- Radiotherapy
- Antihormonal therapy (Tamoxifen)
- Chemotherapy
What is Paget’s disease of the nipple a result of?
Intrepithelial spread of intraductal carcinoma
How does Paget’s appear on histology
- Large pale-staining cells within the epidermis of the nipple
- Limited to the nipple or extend to the areol
How does Paget’s disease present?
- Pain or itching
- Scaling and redness mistaken for eczema
- Ulceration, crusting and serous or bloody discharge
How common is carcinoma of the male breast?
<1% of all breast cancers
What is gynaecomastia?
- The most common clinical and pathologic abnormality of the male breast
- Increase in subareolar tissue
- 30-40% are bilateral
What is gynaecomastia associated with?
- Hyperthyroidism
- Cirrhosis of the liver
- Chronic renal failure
- Chronic pulmonary disease
- Hypogonadism
- Hormone use
- Digitalis, cimetidine, spironolactone, marihuana, tricyclic antidepressants
