Breast Flashcards
How many new breast cancers occur in the UK annually?
What is the risk?
56K - incidence expected to rise by 2%
Risk = 1 in 9
What type of gland is in the breast tissue?
Modified apocrine (sweat) gland
What is an additional nipple called?
Accessory nipple
What is an absence of nipple & areola called?
Athelia
What is an absence of breast tissue, but presence of nipple & areola complex called?
Amastia
What type of breast shape do pre-pubertal girls get as part of development - which can be pathological if it doesn’t progress?
Tubular breast
Upon what do the breasts lie?
Pectoralis major - from 2nd to 6th rib
Which muscle is laterally related to the breast?
Serattus anterior
Which muscles lie inferiorly to the breast?
Rectus abdominus and inferolaterally - external oblique
Where is the nipple found anatomically?
Mid-clavicular line, 4th intercostal space
What lies in the retromammary space?
Fat
How does the breast attach to the pectoral fascia?
By suspensory ligaments extending from dermis of breast to pectoral fascia
What divides the breast tissue into segments?
Suspensory ligaments - called Cooper’s ligaments
What are the sebaceous glands of the areola called?
Montgomery glands
What does the nipple and areola contain?
Sweat glands
Sebaceous (Montgomery) glands
Where does the upper and outer breast extend into? What is this called?
Extends into the axilla
Called axillary tail
What type of cells are the ducts and lobules of the breast tissue lined with?
Columnar epithelium - with myoepithelial cells in the basement membrane
What happens to the breast tissues during the menstrual cycle?
The structure can fluctuate - causing breast tissue to get bigger - causing breast pain. Can get firm lumpy areas due to hormonal changes.
How many lobules are found in each breast?
15-20
What are the ducts of the breast called?
Lactiferous ducts
What do lactiferous ducts converge to become and where?
Converge to become lactiferous sinus - found at the nipple
When do you get hormonal changes in breasts?
Puberty
Menstruation
Lactation
Menopause
What happens to breast tissue in menopause?
The reduction of oestrogen causes much of the glandular tissue to be replaced with fatty tissue (involution).
What happens to the breast during lactation?
The secretory lobules and ducts become enlarged.
Which artery supplies the breast?
What are the 3 main arterial branches of this?
Axillary artery
- Thoracodorsal
- Thoraco-acromial
- Lateral thoracic
What provides 60% of blood supply to the breast?
Internal mammary perforators - these are vessels which arise from the mammillary artery and perforate through the chest wall.
What provides superficial venous drainage of the breast?
Nipple and areola complex venous plexus - drains into intercostal veins
Where does venous drainage of the deep breast tissue go?
Into the axillary, internal thoracic vein and perforating intercostal veins
What are the two types of lymph vessels in the breast?
Superficial and deep - relate to vascular structures - drain into local lymph nodes.
What types of lymph nodes are in the breast?
Local
Regional
Central
What is the path of lymph flow in the breast?
Local –> Regional –> Central –> Venous Circulation (thoracic duct -> left subclavian vein)
Name two locations of superficial lymph nodes in the breast. Which direction do they drain in?
Areola
Subareola
Drain sideways and upwards
Where does the axillary artery arise from?
The subclavian artery
Where do internal mammary lymph nodes (intra mammary lymph) drain?
To lateral aspect and into axillary nodes - again sideways and upwards.
What can happen in inflammatory breast cancer?
The lymphatics can be occluded causing oedema within the breast tissue.
What is peau d’orange appearance associated with?
Breast cancer
Where do lymph nodes of the breast and upper limb drain into?
The axilla
What are the different levels of axillary drainage within the breast?
Lower
Middle
Superior
What is the first lymph node in the chain of lymphatic drainage called?
Sentinel lymph node
How are sentinel lymph nodes used in breast cancer?
Rather than removing all lymphatics - try to identify the sentinel nodes which are involved using blue / radioactive dye injected S/C - can detect which sentinel node has taken up the dye - these can then be removed.
Where does main sensory supply to the breast originate from?
The lower cervical plexus (superior)
Long thoracic nerve (laterally)
Intercostal nerves (2nd-6th)
Where does autonomic supply of the breast originate from?
2nd - 6th intercostal nerves
What supplies sensation to the nipple?
Lateral cutaneous branch of T4
What is the dermatome of the nipple?
T4
