Background and recommendations Flashcards
When should women who were exposed to RT to the chest get screened for breast cancer?
10 years after exposure to RT or age 40, whichever comes first.
What are the key elements of the history to obtain?
- Menopausal status
- Prior RT
- Performance status
- Family history
- Use of exogenous estrogen
- Collagen vascular disease
What are key elements of the breast exam?
- Axillary, SCL node exam
- Breast exam to evaluate tumor size, skin involvement, nipple changes
What are the indications for a breast MRI?
- Multifocal disease
- Plan for neoadjuvant chemotherapy
T1
T1a: >0.1 to 0.5 cm
T1b: >0.5 to 1 cm
T1c: >1 to 2 cm
T2
Tumor more than 2 cm but 5 cm or less
T3
Tumor more than 5 cm
T4a
skin nodules or ulceration
T4b
invasion of the chest wall, not including pectoralis major
T4c
T4a and T4b
T4d
Inflammatory breast cancer
cN1
Movable ipsilateral nodes
cN2
A. fixed ipsilateral axillary nodes
B. clinically apparent IM nodes alone
cN3
A. Infraclavicular nodes
B. IM nodes and axillary nodes
C. Ipsilateral SCL nodes
Stage IIIB
- T4
Stage I
IA: T1 N0
IB: T0-1 N1mi
Stage IIIC
Stage IIIA
- T3 N1 or T1-2 N2
Stage IIA
- T2 N0 or T1 N1
Stage IIB
- T3 N0 or T2 N1
Which DCIS patients can omit RT?
- Women > 70
- Low grade DCIS
- Widely negative margins, > 1 cm
- Willing to take tamoxifen
- Tumor < 0.5 cm
What are poor prognostic factors for local failure after PMRT?
- LVI
- Grade 3
- < 50 or premenopausal
- Tumor > 2 cm
- Close margin, < 2mm
What are indications to treat the CW alone?
- Close margin < 2mm
- 2 poor prognostic factors
What are indications to treat the PL?
- Node positie or T3-4 disease
What are the indications for a PAB?
- 4 or more nodes
- Inadequate axillary node dissection < 10 nodes, ECE
When do you shift the match lines with PMRT?
Shoft the matchlines, laterally first 1 cm at 16 and back medially 1 cm at 32 Gy
How do you develop the scar boost?
Scar + 2 cm margin treated with en face electrons
How much of the breast has to be involved with tumor associated skin edema to be called inflammatory breast cancer?
- 1/3 of the breast
What is the treatment paradigm for inflammatory breast cancer?
- Neoadjuvant chemo with dose dense AC and taxol x 8 cycles
- MRM
- PMRT to CW, PL
What is the treatment paradigm for patients with T0 N+ breast cancer?
- MRM with node dissection
- PMRT to CW and axilla
What is the risk of IM nodes with medial breast cancers and negative axilla?
What is the risk of IM nodes with lateral lesions and negative axillas?
- 5%
CT simulation for intact breast?
- Supine
- Arms up
- Nonindexed bag
- Wing board
- If treating nodes, turn head to opposite side
- Outline the breast with barium
- ABC for left sided breast tumors
What is he dose for intact breast, Canadian fractionation? Boost?
- 42.4 Gy at 2.65 Gy/fx (16)
- 10-16 Gy at 2 Gy/fx
What are patients appropriate for Hypofractionation?
- T1-2 invasive breast cancer
- DCIS
- Separation < 25 cm
How is the boost delivered when treating intact breast?
- 3D conformal RT
What is the standard dose for intact breast? What is the boost dose?
What are the indications for PLI within intact breast RT?
- Node positive
- Presence of poor prognostic factors
- T3-4
Which patients should be considered for chemotherapy?
- Tumors > 1 cm
- Node positive disease
When is oncotype useful?
What is the endocrine therapy of choice for patients with ER positive disease?
- Tamoxifen 20 mg po daily for 5 years for premenopausal
- Arimidex 1 mg po daily for 5 yeats for post-menopausal
What is the dose and regimen for herceptin?
6 mg/kg IV q 21 days for 1 year
What is the standard chemo regimen for most patients?
- Taxotere 75 mg/2m q3 weeks x 4 cycles
- Cytoxan 600 mg/m2 q 3 weeks x 4 cycles
What is the chemotherapy regimen for patients with +HER2/neu positivity?
- Taxotere
- Carboplatin
- Herceptin
When do we begin RT in a patients treatment course?
- 3-4 weeks after chemo
- 4 weeks after surgery
What are contraindications to BCT?
- Mutlicentric tumors
- Diffuse microcalcifications
- Persistent close or positive margins
- Previous CW RT
- Pregnancy
- Scleroderma
- Ratio of tumor size to breast size
Treatment recs for Stage IIIB-IIIC?
Tretament recs for Stage IIB- IIIA
Neoadjuvant chemotherapy surgery (TM or BCT) with surgical axillary staging + RT
TM with surgical axillary staging + RT as indicated. Adjuvant chemo, HT, and/or trastuzumab as indicated
Treatment recs for Stage I-IIA
BCT with lumpectomy and surgical axillary staging + RT (NSABP 06 trial that shows lumpectomy + RT= mastectomy)
Repeat excision indicated for close/positive margins
TM with surgical axillary staging ± RT as indicated*
Adjuvant chemo, hormone therapy, and/or trastuzumab as indicated
Heart constraint?
Mean < 26 Gy
V30<46%
Ipsilateral lung constraint?
V20 < 20%
What are the dose options for patients needing whole breast RT?
- 42.5 Gy at 2.66 Gy/fx
- 50.4 Gy at 1.8 Gy/fx
- 50 Gy at 2 Gy/fx
- 40 Gy at 2.5 Gy/fx
What is the risk for locoregional relaspe after whole breast RT following lumpectomy for T1-2 N0 breast cancers?
At 10 years
- 4.3% to 6.7%
What are the ASTRO requirements for patients to have hypofractionated RT?
- Age 50 or older
- pT1-2 and s/p lumpectomy
- N0
- No chemotherapy
- Along central axis, minimum dose is atleast 93% of Rx dose and no more than 107%
Breast volumes?
Whole breast
A. . PTV: Breast with 5 mm subtracted from the skin
B. Tumor bed
- GTV: Tumor bed including clips and seroma
- CTV: GTV + 1 cm
- PTV: CTV + 0.5 cm
- PTV eval: CTV + 5 cm but confined to breast tissue
What are the doses for partial breast RT?
- Mammosite: 34 Gy in 10 fractions given BID
- EBRT: 38.5 Gy in 10 fractions given BID
Dose constraints when using hypofractionation for whle breast?
- Ipsilateral lung: V16 Gy < 20% and V8 <40%
- Heart (left sided): V20 Gy < 5% and V8<35% and Mean dose < 4 Gy
- Heart(right sided): V20: 0%
- Contralateral breast Dmax: < 2.46 Gy
- Contralateral lung: V4<15%
Dose coverage goals for breast cancer?
- Whole breast PTV: D95% is 95%
- Dmax: 115%
- <30% to recieve more than 100%
- <50% to recieve more than 108%
What boost doses are supported by ASTRO when providing hypofractionated RT?
- 10 Gy at 2 Gy/fx
- 10 Gy at 2.5 Gy/fx
Dose constraint for lungs?
Ipsilateral lung: V20<20%
Total lung:V20<10%
Contrlateral lung: V10<5%
Contralateral breast dose constraint?
Max dose < 3 Gy
V10<5%
Definition of menopause
- Age 60 or higher
- Age <60 and amenorrheic for atleast 12 months
What are the histologic subtypes of breast cancer? Which subtype has the worst prognosis?
Micropapillary (worst prognosis)
Tubular
Mucinous
Cribriform
Invasive papillary
Ductal
Lobular
pN1
pN1mi: 0.2 mm but < 2 mm
pN1a: 1-3 nodes
pN1b: IM nodes by SN Bx
pN1c: 1-3 axillary nodes and IM nodes by SN Bx
pN2
pN1a: 4-9 nodes
pN2b: clinically apparent IM nodes in the absence of axillary nodes
pN3
pN3a: More than 10 nodes or infraclavicular nodes
pN3b: clinically apparent IM nodes with axillary nodes or 4 or more axillary nodes with IM nodes by SN Bx
pN3c: ipsilateral SCL nodes
5 year OS for patients with Stage IV breast cancer?
- 14.8%
5 year OF for patients with Stage III breast cancer?
IIIA: 66%
IIIB: 41%
IIIC: 49%
5 year OS for Stage I?
- 87%
5 year OS for Stage II?
IIA: 81%
IIB: 74%
Treatment of pregnant patients?
1st trimester: