Breast Cancer Flashcards
Aetiology of breast cancers
Most breast cancers are adenocarcinomas (epithelial cancer arising from glandular tissue)
The breast has receptors for hormones e.g. oestrogen, progesterone and prolactin. Progesterone and oestrogen stimulate the alveolar cells to divide.
Linked to mutations in the breast cancer gene BRCA-1 and BRCA-2 (40% lifetime risk of breast/ovarian cancer) and TP53
Also associated with ERBB2 - increases HER-2
Types of breast carcinoma
In-situ (non-invasive)
- Ductal carcinoma in situ
- lobular carcinoma in situ (special type (ST))
Invasive carcinoma
- Ductal carcinoma (No special type (NST)) - most common (70%)
- Lobular carcinoma - 10-15%
- Tubular
- Mucinous
- Basal like cancer (triple negative)
Medullary cancers tend to affect younger patients
Colloid/mucoid tend to affect the elderly
Inflammatory breast cancer
Describe in situ carcinomas
Non-invasive
Cells in the basement membrane of the alveoli
Affected cells begins to grow and replicate uncontrollably
Two types: Ductal carcinoma-in situ and lobular carcinoma in-situ
Ductal carcinoma in-situ
- Tumour cells grow from the wall of the ducts into the Lumen
- Left untreated -> invasive ductal carcinoma
- Comedo necrosis
Lobular carcinoma in-situ (Special type (ST))
- Clusters of tumour cells grow within the lobules but do not invade the ducts and the alveoli enlarge
- They do NOT form invasive lobular carcinoma
- 3 types:
– ER positive and HER2 negative
– HER2 positive and ER positive/negative
– ER negative and HER2 negative
Describe paget disease of the nipple
An eczematoid change of the nipple associated with an underlying breast malignancy
Present in 1-2% of patients with breast cancer (in half of these patients, it is associated with an underlying mass lesion → 90% = invasive carcinoma; 10% = carcinoma in situ)
Cancer cells from a ductal carcinoma in-situ can migrate along the lactiferous duct through pores and onto the skin
The cells release mobility factor which helps them to break into the squamous epithelial cells
Inflammation brings extracellular fluid out through skin breaks -> crusting
Risk factors for breast cancer
Family history
- 3 close relatives (on same side) develop breast cancer
- 2 close relatives develop breast cancer <40
- 1 close relative develops breast cancer <40
- 1 male close relative develops breast cancer
- 1 close blood relative develops bilateral breast cancer
Age (older age)
Increased exposure to oestrogen
- Early age menarche (<13)
- Late age menopause (>51)
- Use of oestrogen-containing medications
- Nulliparity
- First pregnancy >30 years old
- HRT, COCP use (relative risk increase * 1.023/year of use)
- Obesity
Genetic predisposition (BRCA1/BRCA2) - Autosomal dominant
Ionising radiation
Peutz-Jeghers syndrome
Epidemiology of breast cancer
2nd most common cancer in women (can affect men, but rare)
2nd leading cause of cancer deaths in women (after lung) as they do not cause pain or discomfort until they have spread to nearby tissues
Incidence is rising, but mortality is falling
Accounts for 30% of all new female cancer cases
300 men are diagnosed with breast cancer in the UK annually (average age 60-70)
Lifetime risk is 1 in 8
Symptoms of breast cancer
Hard, painless lump or swelling, commonly in the upper and outer part of the breast
Swelling under the armpit (spread to axillary lymph nodes)
Breast is immobile and fixed due to infiltration into the pectoral muscles
Dimpling the skin
Fibrosis of lactiferous ducts and suspensory ligaments -> nipple retraction
Blood-stained nipple discharge
Paget disease - itchy, redness, crusting, rash on nipple-areola
Signs of breast cancer on examination
“Peau D’orange” appearance - dimpling
Hard, painless lump or swelling, commonly in the upper and outer part of the breast
- Single, non-tender, firm, poorly defined margins
- Most common upper outer quadrant
Nipple changes
- Inversion
- Bloody discharge
Swelling under the armpit (spread to axillary lymph nodes)
Breast is immobile and fixed due to infiltration into the pectoral muscles
Dimpling the skin
Fibrosis of lactiferous ducts and suspensory ligaments -> nipple retraction
Paget disease - itchy, redness, crusting
Investigations for breast cancer
All lumps should undergo “triple” assessment:
1. Clinical examination
2. Imaging+ axillary USS
a. <35 → USS
b. >35 → Mammography
c. Implants → MRI
3. Histology/cytology using core biopsy or fine needle aspiration cytology
4. Staging using bloods: FBC, U&Es, LFTs and bone profile if EARLY stages
US:
Ill-defined, hypoechoic mass
Distal acoustic shadowing
Surrounding halo (due to oedema and tumour infiltration)
Abnormal axillary nodes
Core biopsy: confirm malignancy and determine receptor status
Who needs referral to a 2WW clinic for breast cancer
> 30 with an unexplained breast lump
50 with any of the following in ONE nipple only: discharge, retraction, other changes
Skin changes suggestive of breast cancer
30 with unexplained lump in the axilla
2WW is not needed for <30yo with an unexplained breast lump ± pain
What would be seen on mammogram for invasive ductal carcinoma
Invasive Ductal Carcinoma
Ill-defined or spiculated mass
Parenchymal distortion
Overlying skin thickening
Malignant calcifications
Enlarged axillary lymph nodes
How does receptor status impact grade
Low grade: ER/PR +ve, HER2 -ve
High grade: ER/PR -ve, HER2 +ve
Basal like carcinoma: ER/PR/HER2 -ve (triple negative)
Management for breast cancer
Surgery: MASTECTOMY OR WIDE LOCAL EXCISION
Clinical axillary lymphadenopathy?
YES → axillary node clearance (possible lymphoedema)
NO → USS and SLNB ± axillary node clearance
Radiotherapy: adjuvant post-surgery
Following mastectomy with high risk of local recurrence (involved margins, vascular invasion, heavily node positive, dermal invasion)
- Recommended after WLE
- Recommended after mastectomy if T3 or T4 or ≥4 +ve LNs
Hormone therapy (if ER +)
- Pre-/peri-menopausal → tamoxifen (SERM)
Post-menopausal → anastrozole/letrozole (aromatase inhibitor)
Biological therapy (HER2 +) → Trastuzumab (Herceptin)
Chemotherapy: FEC-D chemotherapy regime
- Neoadjuvant or adjuvant
What are the indications for mastectomy vs wide local excision
Mastectomy:
Multifocal tumour
Central tumour
Large lesion in small breast
DCIS >4cm
Patient choice
Wide Local Excision:
Solitary lesion
Peripheral tumour
Small lesion in large breast
DCIS <4cm
What are the indications for chemotherapy in breast cancer
Adjuvant therapy:
Young age (especially less than 60)
Axillary node positivity
A large tumour
Histological features such as Grade 3 and/or lymphovascular invasion
Negative Oestrogen receptor
