Week 7 Flashcards
How many secretory lobules make the secretory tissue in the breast?
15-25
What are Cooper’s suspensory ligaments and why are they important clinically?
Condensations of connective tissue in the breast that form septa
Extend from the dermis of the skin to the deep fascia overlying the muscle of the anterior chest wall
Clinically important because if a mass grows within the breast, this may cause the breast to “pucker” at a certain point, reminiscent of the peel of an orange (peau d’orange)
What is the name of the basic functional secretory unit of the breast?
What is it made up of?
The terminal duct lobular unit (TDLU)
Made up of the lobule and the extralobular terminal duct
What type of cells surround the secretory cells of the acinus (cluster of cells that represents a berry)?
What, in turn, surrounds these cells?
Myoepithelial cells surround the acinar cells, which are in turn surrounded by the basal lamina
What types of cells line the acini?
What type of cells line the inside of larger ducts, such as a lactiferous duct?
Secretory epithelial cells line the inside of the acini and can be either columnar or cuboidal
The epithelium lining the inside of ducts also varies from a thin stratified squamous epithelium to stratified cuboidal epithelium
What other tissue type resembles breast lobules, and many believe is the evolutionary source of mammory glands?
Sweat glands
Describe the structure of the nipple
Lined by a thin, highly pigmented keratinised stratified squamous epithelium
Core of dense irregular connective tissue mixed with bundles of smooth muscle fibres (allows for nipple erection)
Core also contains lactiferous ducts, each serving one lobe of the breast
Several sebaceous glands are also present and end directly on the surface of the skin (Montgomery glands - somewhere between being milk-producing and sweat-producing), function to keep the areola and the nipple lubricated
How does the breast change in the luteal phase?
The epithelial cells increase in height
The lumina of the ducts becomes enlarged
Small amounts of secretions begin to appear in the ducts
What dramatic changes occur in the breast following pregnancy?
Think 1st, 2nd and 3rd trimester
Which hormones cause this?
1st trimester - elongation and branching of the smaller ducts, as well as proliferation of the epithelial cells and myoepithelial cells
2nd trimester - development of glandular tissue and differentiation of secretory alveoli. Plasma cells and lymphocytes also penetrate nearby connective tissue
3rd trimester - maturation of secretory alveoli, development and maturation of rough ER
Connective tissue and adipose tissue amounts decrease
These changes are caused by oestrogen and progesterone
Describe the composition of human breast milk
How does this differ to cow’s milk?
Approximately…
88% water
1.5% protein (mostly lactalbumin and casein)
7% carbohydrate (mainly lactose)
3.5% lipid
Small amounts of ions, vitamins and IgA
Cow’s milk has a much higher % of casein
Lipid secretions of breast milk are secreted by ____
Proteins in breast milk are secreted by ____
Lipids are secreted by eccrine secretion
Proteins are secreted by merocrine secretion
How does the mammary gland change following menopause?
Secretory cells of the TLDUs (terminal ductal lobular units) degenerate leaving only the ducts
Fewer fibroblasts and reduced collagen/elastic fibres in the connective tissue
What cell type in the breast appears to be the most common site for breast cancer?
Ductal cells (forming ductal carcinoma)
What are the components of the ‘triple assessment’ when assessing breast disease?
Clinical
- history
- examination
Imaging
- mammography
- USS
- MRI
Pathology
- cytopathology
- histopathology
How is breast disease classified…
a) by cytopathology
b) by histopathology?
What is the key difference?
a) cytopathology
- C1 - unsatisfactory
- C2 - benign
- C3 - atypia, but probably benign
- C4 - suspicious of malignancy
- C5 - malignant
b) histopathology
- B1 - unsatisfactory/normal
- B2 - benign
- B3 - atypia, but probably benign
- B4 - suspicious of malignancy
- B5 - malignant
- 5a - carcinoma in situ
- 5b - invasive carcinoma
Key difference is histopathology outlines if disease is confined or if it has started to spread
Ducts are continuous with the nipple and external skin. As such, how might ductal carcinoma initially present?
What is this called?
May present with blood/discharge or dry skin/eczema
If dry skin/eczema is seen, this is Paget’s Disease of the Breast
Name some non-neoplastic forms of breast disease
Gynaecomastia
Fibrocystic change
Hamartoma
Fibroadenoma a.k.a. breast mouse
Sclerosing lesions (sclerosing adenosis, radial scar/CSL)
Lipoma
Name some inflammatory forms of breast disease
Fat necrosis
Duct ectasia
Acute mastitis/abscess
What are the two forms of benign breast tumour?
Phyllodes tumour
Intraduct papilloma (most common cause of bloody nipple discharge)
Importantly, while both are considered to be benign, they exist on a spectrum and have the potential to become malignant
In gynaecomastia, what type of growth is seen?
What are some of the associated risk factors for developing this condition?
Ductal growth is seen without lobular development
Risk factors - exogenous/endogenous hormones, cannabis, prescription drigs, liver disease (causing raised oestrogen)
What is fibrocystic change?
How common is it and in what age group is it seen?
Development of ‘lumpy’ or ‘doughy’ areas within the breast that may be cystic or solid
Very common, and is seen in women aged 20-50
May be associated with some pain, and can also be seen to be worse around menstruation
What are the risk factors for developing fibrocystic change in breasts?
Anything that involves more time ovulating
Early menarche
Late menopause - condition usually resolves following menopause
Menstrual abnormalities
NB - these are also risk factors for breast cancer!
What is a hamartoma?
Circumscribed lesion composed of cell types normal to the breast, but present in abnormal proportion or distribution
What is a fibroadenoma also referred to?
Are they common?
Which group experiences these more frequently?
Fibromadenomas also called “breast mouse”
Very common and usually solitary
More common in African women
How would a fibroadenoma be described in terms of palpation?
Circumscribed
Rubbery
Painless, firm, discrete mobile mass
What is the size cut-off for a fibroadenoma to be excised via vacuum biopsy?
2cm - if greater than 2cm, has to be removed via surgical excision
What are sclerosing lesions of the breast?
What are the two main types?
Benign disorderly proliferation of acini and stroma that may cause mass or calcification. Usually asymptomatic but may cause pain or tenderness. Most common in women in their 30s and 40s but can occur anywhere from 20s-70s
- Sclerosing adenosis
- Radial scar/complex sclerosing lesion
What is the size cut-off at which point a radial scar becomes a complex sclerosing lesion?
Radial scars - 1-9mm
Complex sclerosing lesions - >10mm
What’s the diagnosis?…
- Pain and acute episodic inflammatory changes
- Bloody and/or purulent discharge
- Possible nipple retraction and distortion
- Formation of fistulae
- Associated with smoking
Duct ectasia
- sub-areolar duct dilatation
- periductal inflammation and fibrosis
- resultabt scarring and fibrosis
Describe the let down reflex
- baby suckling triggers mechanoreceptors in nipple, which act on higher brain centres via ascending sensory information. Higher brain centres are also triggered by the sound of the baby’s cry
- Hypothalamus signals anterior pituitary to release prolactin and posterior pituitary to release oxytocin
- Prolactin causes milk secretion
- Oxytocin causes smooth muscle contraction
Lobular in situ neoplasia has 2 historic entities, dependent on the amount of the lobule involved. What are these two entities, and what is the % cut-off?
If <50% of lobule involved - Atypical Lobular Hyperplasia (ALH)
If >50% of lobule involved - Lobular Carcinoma in Situ (LCIS)
Where in the breast does ductal carcinoma in situ arise?
What % of breast malignancies are DCIS?
What feature of DCIS’ typical appearance means that surgery is usually the go-to option?
DCIS arises in the terminal duct lobular units (TDLUs)
15-20% of breast malignancies are DCIS
DCIS tends to be unifocal meaning surgical treatment is usually opted for
What are some of the risk factors for developing breast cancer?
Increasing age
More menstrual cycles - young at menarche, late menopause, nullparity, never breastfeeding (having children and breastfeeding are protective)
Hormones - endogenous, exogenous (OCP, HRT)
Previous breast disease
Lifestyle - obesity, alcohol consumption, poor diet, NSAIDs, smoking
Genetics - BRCA1, BRCA2, TP53, PTEN
What are the 3 criteria that breast carcinoma can be graded on?
What are the min and max scores?
- Tubular differentiation (1-3)
- Nuclear pleomorphism (1-3)
- Mitotic activity (1-3)
Min score = 3 (good), max score = 9 (bad)
Score 3, 4 or 5 = Grade 1
Score 6 or 7 = Grade 2
Score 8 or 9 = Grade 3
What neoadjuvant treatments can be given to treat breast cancers?
What is the aim?
Chemotherapy (FEC100 and taxane) +/- Herceptin
Aromatase inhibitors (Letrozole) - reserved for post-menopausal women
These treatments aim to shrink the tumour in size, meaning that breast conserving surgery can become an option again
What are some of the reconstructive options when performing a mastectomy?
External prosthesis
Implant only (+/- autologous cellular matrix)
Latissimus dorsi pedicled flap (LD flap) +/- implant
Deep Inferior Epigastric artery perforator (DIEP) free flap
Inferior (or superior) gluteal artery perforator (IGAP) free flap
Also: TUG flap, PAP free flap, SGAP flap
