Breast cancer Flashcards
what is the standard of care for tx of DCIS
breast conserving surgery followed by post-op RT or mastectomy
when would u not give post-op RT for DCIS
if the tumour is low grade
what is the role of post op RT for DCIS
to reduce recurrence
what tx is delivered if a pt with DCIS has multi centric or high risk disease
whole breast irradiation or mastectomy
dose DCIS require LN tx
no, axilla direction or irradiation is not needed as risk of axillary involvement being <4%
what is a DCIS
Ductal carcinoma in situ
usually contained within one segment (1/4) of the breast
tumour is confined to the duct
what is IA
Invasive adenocarcinoma
that has invaded outside of ducts and lobules
what is the sanded of care for IA tumours <3cm
breast conserving surgery - usually wide local excision
followed by post op RT
what tx is given for IA breast cancer if margins of WLE are positive
WLE tx is given again
if margins are still positive then mastectomy is given
what is the standard of care for IA tumour >3cm
preoperative chemotherapy or HT given to shrink tumour followed by possible breast conserving surgery
or mastectemy and axillary clearance if no response from tumour
what is the standard tx for axillary LN
initllay was the use of axillary dissection surgery - however causes increased risk of lymphodema and frozen shoulder (reduced mobility)
so now only used for advanced disease
instead axillary irradiation can be given to reduce recurrence and has less risk of lymphoma and frozen shoulder
when is IMC irradiation given (3)
if the tumour is very medial/central position
if >4axillary LN are involved
if pt at high risk of local recurrence
when is IMRT tx delivered for breast cancer and 2 advantages
IMRT tangential fields are delivered for whole breast irradaiation
Have helped reduce hotspots due to varied intensity throughout beam
Allowed better variation for different tissue densities of breast
2 examples of VMAT used for breast cancer
bilateral breast irradiation with single iso
SIB tx
what is SIB and how has it changed
simultaneous integrated boost
changed from sequential boost of 15gy 5# adjuvant to whole breast tx to integrated within tx of standard 48Gy in 15#
when is SIB considered (3)
majority of pts receiving VMAT tx have SIB
if margins were close
unfavourable features (T3/T4/HR recurrence)
what is partial breast irradiation
the delivery of radiation to the tumour bed or surrounding tissue post surgery instead of the whole breast - via EBRT,BT or IORT
why is Resp. gating used for breast cancer
if tx close to heart (Left side or deep seated) then deep inspiration breath hold (DIBH) or automated breathing control (ABC) allows the heart to be pushed maximally posteriorly away from tx field reducing dose received.
also allows pt to reproduce position more accurately and for safer tx delivery
what is the common standard of care for locally advanced disease (breast cancer)
neoadjuvant chemotherapy- to debunk tumour prior to surgery
surgery - mainly given as mastectomy or removal of residual mass post chemo
RT- post op rt or if no response from chemo then RT given radically instead as 40Gy in 15#
what are the 3 grade of DCIS
low garde
intermediate grade
high grade
what are the 2 subgroups of IA breast cancer
no special type
special type - tubular/mucoid/papillary etc.
what are the 3 grades of IA
grade 1-least malignant
grade 2
grade 3- most malignant
what are the 5 TNM stages for breast cancer
Tis= DCIS
T1= tumour <2cm
T2=in breast, LNs or both
T3=locally advanced in LN near to breast, skin or chest wall
T4=advanced mets - brain/lung/bone
give 4 aetiological factors for breast cancer
obesity
alcohol
contraceptive pill
HRT
age
gentic history -BRCA
ethnicity - white
tissue density
