Anatomy and Physiology of the Breast Flashcards
What is the most common and most affective screening tool of breast cancer?
Mammography
What is the first imaging sign in mammography of a developing malignancy?
Microcalcifications
Match radiopaque and radiolucent with fatty and dense breasts
Dense = radiopaque (x-ray cannot penetrate through)
Fatty = radiolucent
T or F? Mammography is good at detecting if a lesion is solid or cystic?
FALSE: cannot be determined which is when they send the patient for an ultrasound
Is the breast an endocrine or exocrine gland?
Exocrine
What is the primary function of the breast?
To produce milk
What elements of the breast tissue primarily function to produce and convey milk?
Glandular tissue
What do stromal elements of the breast consist of? (5)
- CT
- Fat
- Blood vessels
- Lymphatics
- Nerves
Unilateral early ripening or unilateral premature thelarche usually occurs prior to what age?
8 years
What is precocious puberty?
Development of both breast by the age of 8
What is the most common nipple variant?
Polythelia (accessory nipple)
T or F? Congenital nipple inversion is a normal variant?
TRUE
What type of glands are found at the areola?
Montgomery glands - secrete oil during breast feeding
What arteries supply the medial and lateral part of the breast?
Medial: Internal thoracic artery supply
Lateral: Axilla (lateral thoracic and thoracoacromial artery)
What veins drain the breast? (3)
- Axilla
- Internal thoracic
- 2-4th intercostal veins
Lymph in the breast flows through the intra-mammary nodes and lymph vessels into what?
Subareolar plexus
Where are the intra-mammary nodes of the breast especially located?
UOQ near axilla
Are intra-mammary nodes or axillary nodes more commonly seen on ultrasound?
Axillary
How big are intra-mammary nodes usually?
< 1cm
What nodes account for most of the lymph drainage?
Axillary (lateral pathway)
What is the first lymph node which drains a cancerous tumor and is at most risk for metastasis?
Sentinel Lymph Node (SLN)
Where is the sentinel lymph node (SLN) located ?
Lower axillary
What type of ligament connects the breast to the skin?
Coopers’ ligaments
What is another name for the fibrous tissue of the breast?
Suspensory ligaments
T or F? Both males and females contain coopers’ ligaments in the breast?
FALSE: men do not
What provides support to the breast?
Coopers’ ligaments
Portions of mammary tissue can extend into the axilla, which is called what?
Axillary tail AKA tail of Spence
What is the axillary tail also called?
Tail of Spence
How many overlapping lobes does the mammary layer consist of?
15-20
How many TDLU’s are contained in each lobe?
20-40
What does a TDLU consist of?
- Lobule
- Extralobular terminal duct
What are the SMALLEST functional units of the breast?
Acini
When do ductules turn into acini or alveoli?
During pregnancy
Where does most pathology of the breast arise from?
TDLU’s
Where are TDLU’s most commonly found? (what breast layer)
Mammary
What is the pathway of the ductal system from smallest to largest? (6)
Acini –> intralobar terminal duct –> extralobar terminal duct –> lactiferous duct –> lactiferous sinus –> nipple
What type of breast tissue is most common in males?
Fatty tissue
What are the two most common breast conditions in men?
- Gynecomastia (benign breast enlargement)
- Cancer
Which breast layer contains fat?
All of them
What hormone(s) stimulate stromal & ductal growth and development as well as altering body fat composition?
Estrogen
What hormone(s) are responsible for giving the nipple its colour?
Estrogen and progesterone
What hormone triggers the growth of alveoli?
Progesterone
What hormone stimulates milk production?
Prolactin
What hormone triggers milk ejection?
Oxytocin
What is the pre-mammary layer also known as?
Subcutaneous fat layer
In which layer of the breast are Cooper’s ligaments best seen?
Premammary
Which breast layer contains the glandular tissue?
Mammary layer
Which layer will you see lactiferous ducts?
Mammary layer
Where is most glandular tissue found in the breast? (hint: quadrant)
UOQ
What is contained in the retro-mammary layer?
Fat and ligaments (suspensory ligaments)
Fatty replacement of parenchyma occurs with what factor?
Increasing age
A lesion sits at 10:00 in the right breast- which quadrant is the lesion in?
RUO
A lesion sits at 7:00 in the left breast- which quadrant is the lesion in?
LLI