Breast Flashcards
ASTRO APBI “Suitable” Criteria
age ≥50
Tis or T1
margins ≥3 mm
ASTRO APBI “Cautionary” Criteria
40-49 years and all other suitable criteria are met
OR age ≥50 and at least one of:
size 2.1-3.0 cm
T2
margin <2mm
limited/focal LVSI
ER-
ILC
any DCIS ≤3 cm if suitable criteria not met
EIC ≤3 cm
ASTRO APBI “Unsuitable” Criteria
age <40
positive margins
DCIS >3cm
age 40-49 and does not meet cautionary criteria
Breast: Workup
H&P with breast/node exam (extra history: prior RT, collagen vascular dz, menopausal status, pregnancy status) Labs: CBC, LFTs, alk phos, beta-HCG. BRCA for young age or direct family history Imaging primary: diagnostic mammogram (magnification for calcs, spot compression for questionable mass), US with core needle bx. Evaluation of ER/PR/Her2. If invasive breast cancer patients with ER/PR+ and tumor size 0.5 cm or greater, order Oncotype MRI potential indications: DCIS, unknown primary (axillary node or pageats), neoadjuvant chemo planned, dense breasts, to assess for extent of multicentric or multifocal disease especially if unsure about lumpectomy Imaging staging: CXR. Bone scan and CT only for Stage III. PET scan increasing in use
Breast: Contraindications to lumpectomy (RT)
Absolute: pregnancy, large surgery that would result in poor cosmesis, diffusely/persistent positive margins, diffuse calcifications
Relative: prior RT, active connective tissue disease (esp scleroderma and lupus), T3 category 2B, positive margin (prefer re-excision), BRCA or other genetic predisposition
Breast: 3D conformal tangents
Supine, breast board, wire scar and both breasts, bolus if skin involvment. Set tangents in middle of field, put iso in middle of tangents. Add 0.7cm for breast PTV and crop breast PTV eval off chest wall and 0.5cm off skin.
Breast: Boost setup
Seroma plus clips, 1 cm CTV, 0.7cm PTV. Use 2-3 field photons or electrons to 80-90% idodose line.
Breast: when to treat nodes post-lumpectomy
One way: 4 nodes positive or 1-3 nodes and medial tumor
Another way: any nodes positive
Breast: indications for chemo
Her2+
triple negative
ER/PR+ that is >0.5 cm and had high Oncotype
node positive
Breast: considerations for each case
Should I check BHCG?
Should I do neoadjuvant chemo?
Is lumpectomy or mastectomy indicated?
Is chemo indicated?
Special Her2+ chemo?
Is RT indicated?
Should I boost?
Is RNI indicated?
Is adjuvant HT indicated?
Breast: DCIS treatment paradigm
Lumpectomy or total mastectomy (consider SLNBx if mastectomy) Strongly favor XRT for grade 3, ER/PR negative, or young age 40Gy/15fxs +/- boost (grade 3, <2mm margin, comedonecrosis, age<50, ER/PR negative) Adjuvant Tam. Aromatase inhibitor if postmenopausal and age 50-60 (NSABP-35)
Breast:conventional whole breast dosimetry (coverage, max hot spot, lung V20, heart mean, contralateral breast max)
95/95 coverage of PTV eval
max hot spot 107%
no large 105% hotspots
lung V20<30%
heart mean <4Gy
contra breast max <4Gy
BOOST:
50% of breast gets at least 90% dose <1/3 breast gets 100%
Breast: follow up
imaging and/or exam every 6 months for two years then anually annual GYN exam if on tamoxifenimaging and/or exam every 6 months for two years then anually annual GYN exam if on tamoxifen
Breast: indications for hormones
ER+ Premenopausal: tamoxifen 10 years OR tam then AI for 5+5 years if becomes postmenopausal
Postmenopausal: AI for 5 years
Breast: hypofractionation dosimetry
95/95 coverage
105% volume should be minimized
contralateral breast <2.4 Gy
<15% ipsi lung>16 Gy
<10% contra lung>4 Gy
<5% of heart >16 Gy if left sided
Breast: outcomes for early stage
10yr LR 6%
10yr OS 85%
(EBCTCG)
Breast: chemo regimens
Her2-: ddAC (q 2 weeks x 4 cycles) + Taxol, neulasta support
Her2 +: AC/paclitaxol/herceptin (not dose dense) give taxol 4mg starting dose with first day of taxol, and continue weekly x 1yr
Breast: APBI brachy dose, volumes, dosimetry
34Gy/10fxs BID over 5 days
If using SAVI then may need to place dummy at time of surgery CT simulation with breast board.
CT sim or scout prior to each treatment to confirm position of device. 1.5cm expansion, crop 0.5cm from skin
Mammosite/SAVI (NSABP-B51)
skin<145% V90>90% V200<20cc V150<50cc no criteria for lung no criteria for rib
Breast: APBI EBRT dose, volumes, dosimetry
- 5Gy/10fxs BID over 5 days
- 5cm CTV
- 0cm PTV
crop PTV eval off chest wall and 0.5cm skin
EBRT (NSABP-B51)
ipsi lung: V30% dose<15%
contra lung: V5% dose<30%
Heart, right: V5%<5%
Heart, left: V5%<40%
Breast: double isocenter narrative
The patient would be placed in the supine position with breast board. A supraclavicular field would be created using a half beam block at the inferior edge with the isocenter placed at this level. For the tangent field, a second isocenter would be placed at the midpath of the tangents, about 1 cm anterior to the chest well. For the tangents, the couch would be moved away from the gantry and collimator rotated to align the cranial edge of the tangents with the supraclavicular field. The lung would be blocked using MLCs. Alternatively, can rotate the collimator so that the jaw of the collimator blocks the lung in the tangent field, then use MLCs to block the portion of the tangents overlapping the SCV field.
Inflammatory breast cancer: workup, treatment paradigm
PET and CT C/A/P neoadjuvant chemo -> mastectomy -> PMRT with regional node irradiation 50 Gy plus 10-16 Gy boost, bolus skin!
For poor response to neoadjuvant chemo, consider pre-op treatment with 51 Gy in 1.5 BID plus 15 Gy boost OS 50%
Breast: ddAC+T dose and schedule
Doxo 60mg/m2 and Cyclophosphamide 600mg/m2 on day 1. q14 days x 4 cycles with neulasta support.
Paclitaxel 80 mg/m2 weekly x 12 week.
Or Paclitaxel 175 mg/m2 day 1, Q14 days x 4 cycles.
Breast: chemo regimen for Her2+
AC (60/600) q 3 weeks x 4 followed by paclitaxel weekly (80) x 12.
Start Trastuzumab 4mg/kg with the first dose of paclitaxel then 2 m2/kg weekly during paclitaxel. Then every 3 weeks (6mg/kg) for 1 year.
If doing pertuzumab: Loading dose of 840 mg pert and 8 mg/kg tratuzumab followed by 420 pert and 6 mg/kg tratuzumab every 3 weeks, with 80 mg/m2 paclitaxel weekly for FOUR CYCLES then back to q3 week tratuzumab until 1 year tratuzumab TNBC or BRCA mutation: use platinum regimen
Breast T1a
>1mm - ≤5mm
