10 - Breast Anatomy Flashcards
describe the epithelial structures of the breast?
ducts
glandular lobules
describe the mesenchymal structures of the breast?
fat tissue
fibrous tissue
when does breast structure change?
with age
during pregnancy
how many lobes does each breast have and how are they arranged?
8-10 lobes each
arranged like petals of a flower
what is within the lobes?
lobules
what is present in the lobule?
bulbs at the end of each lobule which produce milk
what are the breasts in both sexes before puberty?
ducts
how to describe the growth of breasts between aged 2 and the end of puberty?
proliferation
how to describe the growth of breasts between the end of puberty and after pregnancy?
proliferation and differentiation
2 aspects of the lymphatics of the breast?
lymph ducts
lymph nodes
what do lymph ducts of the breast do?
drains fluid that carrier white blood cells from breast tissue into lymph nodes in axilla
what do lymph nodes of the breast do?
filter harmful bacteria and fighting off infection
during breast development, when do mammary crests appear?
@ week 4
what 3 types of factors determine breast size and shape?
genetic
racial
dietary
describe 2 general features of breasts?
modified and highly specialised sweat glands
no special capsule
describe extent of breasts in terms of ribs?
2nd/3rd rib to 6th rib
describe transverse location of breasts?
sternal edge to midaxillary line
what does the retromammary bursa (space) allow?
some degree of movement
what fascia do the breasts lie on?
deep pectoral fascia covering pectoralis major and the fascia covering the serratus anterior
how is the breast attached to the dermis?
suspensory ligament of cooper
location of nipple?
4th IC space
what does the skin covering areola contain?
sweat and sebaceous glands
name 4 quadrants of breast in a clockwise order?
superomedial
inferomedial
inferolateral
superolateral
what is the axillary tail?
extension of breast tissue in the supero-lateral quadrant
in the male breast, when is there a temporary enlargement?
newborns and during puberty
athelia?
absence of nipple
amastia?
absense of breast
polymastia?
extra breast
polyelia?
an extra nipple
name 3 arteries supllying breast?
Thoraco acromial artery
Lateral thoracic artery
Internal mammary (thoracic) artery
where do veins of the breast drain into?
axillary and internal thoracic veins
what are the nerves of the breast?
Anterior and lateral cutaneous branches of 4-6th intercostal nerves
what do the nerves of the breast carry?
convey sensory fibers to the skin of the breast
also carry sympathetic fibres to the blood vessels and to the smooth muscle around the nipple
why are lymphatics of the breasts so significant?
metastatic dissemination occurs primarily by the lymphatic routes
describe the lymphatics of the breast?
branch extensively and do not contain valves
where does >75% of lymph come from in the breast?
lateral quadrants - to axillary lymph nodes
where can other 25% lymph drain to?
some lymph drains directly to supraclavicular or inferior cervical nodes
Lymph from medial quadrants – parasternal or to opposite breast
what is sentinel lymph node biopsy used for in breast cancer?
Lymphatic mapping & staging of patients
what is used to locate the sentinel lymph node?
radiolabelled colloid
which lobular unit is the functional milk secretory component of the breast?
the terminal duct lobular unit
what do the neonatal breast contain?
lactiferous ducts and no alveoli
what does the slight enlargement of breast tissue prepuberty show?
the growth of fibrous stroma and fat
describe 3 changes during puberty?
branching of lactiferous ducts
alveoli
accumulation of lipids in adipocytes
describe 2 post-menopausal changes to breasts?
Progressive atrophy of lobules and ducts
Fatty replacement of glandular tissue
describe 2 imaging diagnostic methods for breast cancer?
mammography
US
describe 2 diagnostic methods for breast cancer?
fine needle aspiration cytology
core biopsy
