Breast

Question 1

S&S

Answer 1

Painless 0.5cm palpable lump

Question 2

Epi/Eti

Answer 2

Most common incidence in women
life style-early menarche late menopause
nulliparous women
BRCA 1+2
1 in 8 women

Question 3

BRCA 1 & 2

Answer 3

5-10% of breast cancers are inherited
10-15% ovarian cancer
increase risk of developing breast or ovarian cancer at an early age i.e. before menopause

Question 4

Prognostic indicators

Answer 4

LN status & tumour size

Question 5

Pathology

Answer 5

invasive infiltrating ductal carcinoma 70%

invasive lobular carcinoma 5-10%

Question 6

Dose

Answer 6

Tans:
45-50/25 fx (200/fx)
WBRT
4256/16 (266)
2600/5
10-16Gy/4-8 e for boosts

S/C:
45/25 -own prescription

Question 7

Anatomy

Answer 7

Extends from 2nd-6th rib
80% adipose & CT
20% glandular
15-20 lobes

Quadrants
UOQ-50% (lateral)
Nipple-18%
UIQ-15% (medial)
LOQ- 11% (lateral)
LIQ-6% (medial)

Question 8

Multifocal vs multicentric

Answer 8

multifocal-contained near primary tumour in same quadrant (better prognosis)

multicentric- tumours that appear in several quadrants

Question 9

ER/PR status and hormones

Answer 9

post-menopausal women tend to be positive
allred score b/w 0-8-higher the better
if positive means they will respond to hormones

Tamoxifen: Pre +post menopause (blocks estrogen)
Letrozole: post-menopause (lowers estrogen)

Question 10

immunotherapy

Answer 10

Trastuzumab (Herceptin)

only works on herceptin2+

Question 11

Stage 0 TIS

Answer 11

RT: Breast/CW
Chemo: no chemo, it is reserved for high risk pts
Sx: lumpectomy +RT OR mastectomy NO RT

Question 12

Stage I

TIN0M0

Answer 12

RT: Breast/CW
no nodal involvement
tan fields only

Chemo: Tumors >1cm

Sx: Lumpectomy + RT OR mastectomy NO RT unless tumour >2cm)

Question 13

Stage II

T0N1M0, T1N1, T2N0, T2N1, T3N0

Answer 13

RT: Breast/CW
S/C + Ax would depend on # of axillary nodes involved

Chemo: useful in reducing relapse rates

Sx: Lumpectomy + RT
Mastectomy +RT
<2cm w/ positive nodes 2-5cm

Question 14

Stage III

T0N2, T1N2, T2N2, T3N1, T3N2, T4N2, Any T N3

Answer 14

RT:
RT AFTER sx
Breast/Cw + Sc/Ax
would include Ant S/c and post field

Chemo: chemo prior to sx

sx: mastectomy

Question 15

WBRT tx borders

Answer 15

The purpose of this field arrangement is to maximize coverage to breast tissue and minimize the dose to lung and heart
Sup; sup extent of palpable breast tissue, edge of head of clavicle
Inf: 2cm inf of inframammary fold
Med: midline of pt (palpation of sternal notch and xiphoid process)
Lat: midaxillary line, 2dcm beyond breast
Ant: Flash to include entire breast
Post: include CW; 1-2cm post edge of ribcage

Question 16

S/C + Ax field border

Answer 16

Sup: 5cm sup to SSN and avoiding flash
Inf: matching Tan sup border
Med: Mid SSN
Lat: 1cm beyond head of humorous

Question 17

Major obstacles to providing optimal position

Answer 17

Size and shape of breast pt
lack of mobility
age
anatomical concerns
breast positioning

Question 18

PBI

Answer 18

partial breast irradiation\

• used in early stage
• tx design requires visualization of lumpectomy cavity and intentionally placed surgical clips
• wire placed on lumpectomy scar
• The ratio of the partial breast target volume is less than 25% to receive dose requirement

Question 19

DIBH

Answer 19

deep inspiration breath hold

cardiac volumes that receive more than 50% of prescribed dose

Question 20

Acute side effects

Answer 20

Breast and chest swelling
cough/SOB
local hair loss
skin rxn
fatgiue