Breast Imaging Flashcards
(42 cards)
what types of imaging are part of the triple assessment in the breast clinic?
mammography and US
how is the appearance of a lesion classified on imaging in triple assessment?
1-5 (5 being malignant)
what is a mammography?
low density x-rays
breast is compressed to allow these to easily pass through
provides contrast between tumour and fat
how many projections are used in mammography?
2 projections
- oblique
- craniocaudal (CC) - looking from top to bottom of pt
describe what white and dark tissue represents on a mammogram?
white - fibroglandular tissue
dark - adipose tissue
where is most fibroglandular tissue (white on mammogram) found in breast?
mostly in lateral part of breast
describe the sensitivity of mammography in very fatty breast vs very dense breast?
fatty = high
dense = low (poor contrast)
breast density increases with age - true or false?
false - breast density decreases with age
what factors can change the rate at which breast density decreases?
weight
HRT use
tamoxifen use
people with higher breast density are at a higher risk of breast cancer in their lifetime - true or false?
true
what are the advantages of mammography?
images the whole breast at once
high sensitivity for DCIS and invasive cancers
has shown to decrease population mortality through its use in screening
high reattendance rates to screening
what are the disadvantages of mammography?
false positives
overdiagnosis
ionising radiation
uncomfortable for some
calcification may be identified on mammography at screening - what conditions can cause this?
duct ectasia
DCIS
tomosynthesis is a feature of mammography - what does it do?
allows slices of breast to be imaged (like CT) - increases sensitivity
how can lesions be enhanced on mammography?
contrast
given IV
usually iodinated
2 images taken - 1 before and one after contrast
what is US used for in breast clinic?
confirm lumps seen on mammography if patient is symptomatic image guided biopsy inflammation breast problems in pregnancy (mammogram not helpful here as breast too dense)
what are the advantages and disadvantages of using US in breast clinic?
adv
- not uncomfortable
- detects invasive cancer well
- can distinguish cyst from solid lump
disadv
- doesnt pick up DCIS as well as mammography
contrast enhanced US is often used in breast clinic - true or false?
false - not used very often
what is the purpose of elastography?
measures stiffness of tissue
cancers and their surrounding tissues are more likely to be stiff
benign lesions eg fibroadenomas are soft
what are the different probes used for elastography?
strain elastography = probe should be moved to assess lesion
shear wave = probe remains still when assessing lesion
why are cancers usually stiff in comparison to benign pathology?
collagen in stroma becomes
- disorganised
- poorly aligned
- lots of cross linking occurs
the interaction between the tumour and surrounding stroma is important in predicting spread and patient outcome - true or false?
true
tumours with what characteristics are usually stiffer than others?
node positive tumours
large tumours
tumours of high grade
lobular cancers
what are the advantages and disadvantages of MRI in breast cancer?
adv
- most sensitive and accurate for sizing of lesion
disadv
- shows tiny foci of cancers away from main lesion that prompt patients to have mastectomy instead of wide local excision