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Flashcards in Test 4 Deck (170)
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1

One of the most common malignancies in males, older patients and slow-growing (watch and wait in older patients)
Surgery, RT, or hormonal manipulation; no chemo
Castration or hormonal castration
AP/PA and boots nodes
Immobilization: mid-abdomen to feet; knee sponge, rubber band, sandbags, register table, etc.

Prostate cancer

2

65% of prostate cancers occur in men over ___ years old

65

3

3 types of prostate RT

Prostate seeding with iodine or palladium for earlier state disease
EBRT: long treatments
IMRT and VMAT: 3D planning allows conformal dose

4

Combination of medical/hormonal (gonadotrophin-releasing hormone agonist) or surgical castration with an anti-androgen for the treatment of advanced prostate cancer

Maximal androgen blockade (MAB)

5

Luteinizing hormone-releasing hormone (LHRH, ex: leuprolide) and gonadotropin-releasing hormone (GnRH) receptor blockers

Hormonal castration

6

4 things prostate treatment depends on

Patient's age
Stage/aggressiveness of disease
Underlying medical conditions and patient preference
Gleason score (GS)

7

2-10 grade of histology of prostate CA; most common morphology (1-5) + highest grade histology (1-5)

Gleason score (GS)

8

Lateral and posterior borders for prostate cancer

Lat: anterior to pubic symphysis
Post: spare rectum but allow coverage

9

Superior, inferior, and lateral borders for prostate cancer with LN involvement

Sup: mid-sacrum to L5
Inf: 2 cm inferior to prostate or BIT
Lat: 1.5-2 cm lateral to pelvic brim/bony pelvis

10

___ field box VMAT, ___-___ field IMRT for prostate

4, 6-7

11

Less than 35-40% of rectum receiving ___ Gy

60 Gy

12

Seminal vesicles _______ and _______ to prostate

Superior, posterior

13

Prostate ___ cm above urethra

1 cm

14

___ mm margin from GTV and PTV for prostate and ___ mm margin from PTV to block = ___ cm from GTV to block

6 mm
9 mm
1.5 cm

15

Prostate: ___ Gy in 38 days = ___ cGy per fraction

76 Gy
200 cGy

16

Early stage six field prostate and SV dose and total dose

Dose: 5940-6000 cGy
Total: 7000-7400 cGy

17

Prostate dose
LN involvement
Four field pelvis

4500 cGy

18

Prostate dose
LN involvement
Six field prostate and SV

5940 cGy

19

Prostate dose
LN involvement
Six field prostate only total

7200-7400 cGy

20

Prostate clinical trials: 7020 cGy at 270 cGy per fraction = ___ cGy at ___ cGy per fraction

8440 cGy at 200 cGy per fraction

21

Why are the prostate clinical trials effective?

Rad bio effect very similar; adding dose quicker, less doses/treatment time/patient doesn't have to come in as much

22

2 forms of daily IGRT for prostate treatment

US not as common: sonory or iBeam
Gold fiducials

23

Triangulate marks on port film of prostate and make sure all three points are lined up, now used

Gold fiducials

24

Parallel opposed fields not used in IMRT because beams can't face each other or algorithm will fight against itself to get dose to certain area

Optimization

25

If DVH tails off = _______

Hotspots

26

Want critical structures close to ___-axis and to fall off as rapidly as possible on DVH

Y-axis

27

Normal fractionated dose

180-200 cGy

28

Permanent implant takes ___-___ hours to place seeds through _______ and lasts ___-___ weeks

1-2 hours
Perineal
1-2

29

3 radioactive isotopes used in prostate treatments

Iodine-125
Palladium
Iridium

30

Palladium half-life and energy

T1/2: 17 days
E: 21 keV

31

Iodine-125 half-life and energy

T1/2: 59.6 days
E: 28 keV

32

___-___ prostate seeds; low dose range of ___ cGy, high dose range of ___-___ cGy

180-200 seeds
125 cGy
145-160 cGy

33

Which prostate seed source gets higher dose?

Iodine-125 has longer half-life and lower dose rate so it needs a higher dose

34

Which prostate seed source is used in larger volume implant?

Iodine-125 has higher energy and can treat further out; used for larger disease

35

Iodine-125 typical dose, rate, and size

145 cGy rate of 7 cGy/hr and larger volume implant

36

Palladium dose and rate

125 cGy, 19 cGy/hr

37

4 bladder cancer treatments

Cystectomy for early stage disease, carcinoma in situ, etc.
RT for advanced disease or inoperable patients: 3 or 4 field
Intravesical chemo
Combination

38

Chemo instilled directly in bladder

Intravesical chemo

39

What is an example of intravesical chemo?

Bacillus calmette-guerin (BCG)

40

Combination bladder treatment: ___ Gy ___ weeks before partial or radical cystectomy

30 Gy, 2 weeks

41

Initial dose and dose with boost for bladder cancer being treated with RT alone

Initial: 45-50 Gy
Boost: 65-70 Gy

42

2 reasons the bladder is treated empty

Guarantee size
Smaller treatment field

43

AP/PA bladder fields superior, inferior, and lateral margins

Sup: L5-S1
Inf: BOF or more if bladder neck involved
Lat: 1.5-2 cm beyond pelvic brin

44

Lateral bladder fields anterior and posterior borders

Ant: 1 cm in front of bladder
Post: 2-3 cm posterior to tumor, exclude rectum

45

Helps reduce penis/urethra cancer in foreskin

Circumsicion

46

Penis/urethra cancer position

Opposed laterals in prone

47

Penis/urethra cancer initial, boost, and total dose

Initial: 55-60 Gy
Boost: 1000 cGy
Total: 65-70 Gy

48

5 LNs associated with penis cancer

External iliacs
Obturator
Presacral
Inguinal
Pelvic

49

Penis cancer with LN involvement dose for no gross enlargement and for palpable LNs

No: 50 Gy
Palpable: 70 Gy

50

Treatment of choice and treatment for inoperable kidney cancer

Choice: surgery
Inoperable: RT

51

Kidney cancer initial dose to upper abdomen, boost, and total dose

Initial: 5040 cGy
Boost: 540 cGy
Total: 5580 cGy

52

Kidney cancer energy because there's a lot of tissue

10 MV or more

53

Kidney cancer fields

Equal or unevenly weighted fields
AP/PA and obliques

54

What is the dose limit to the contralateral kidney if one has been removed due to kidney cancer?

Under 15-18 Gy

55

What is the side effect from a nephrectomy or radiation nephrectomy?

Hypertension

56

3 structures kidney and ureter involvement treatment portals include

Entire renal fossa
Ureteral bed
Ipsilateral bladder trigone

57

Seminomas of the testis are considered _______

Radiosensitive

58

3 LNs associated with early seminomas of the testis

Periaortic
Ipsilateral renal hilar
Ipsilateral iliacs

59

Unilateral and bilateral testicular treatment field

Uni: hockey stick
Bi: inverted-Y

60

Clam/scrotal shield during testicular treatment for reproductivity decreases internal scatter which could be as high as ___% the total dose

10%

61

Initial dose, fractions, and boost for larger testicular masses

Initial: 20-2500 cGy
Fracts: 10-20 fractions
Boost: 1000 cGy to known mass

62

Length and lateral border for testicular seminoma cancer

Length: top of T10 to top of obturator foramen
Lat: aortic LNs visualized by CT and ipsilateral renal hilar LN about 10-13 cm wide or sides of transverse processes

63

Left sided testicular tumor field

Widened field at level of renal hilar LNs to include these LNs

64

5 breast cancer prognostic factors

LN status: number of axillary LNs involved with tumor very important aspect of staging; sentinel node biopsy and tangents to cover LNs
Tumor extent/size of primary tumor; larger tumor more likely involved with skin, chest wall, etc.
Histology
Receptor status
Flow cytometry

65

Evaluate at least 10 axillary LNs; 3 or less positive LNs = low risk, 4 or more = high risk

Axillary LN dissection

66

5 year survival for breast lesions/tumors smaller than 0.5 cm, over 0.5 cm, less than 2 cm, and greater than 5 cm

< 0.5 cm = 99%
> 0.5 cm = 82%
< 2 cm = 91%
> 5 cm = 63%

67

3 breast cancer histologies

Infiltrating ductal most common
Lobular second most common
Peau d'orange/inflammatory: clinical diagnosis and poor prognosis

68

Receptor status most common in postmenopausal women, slow growing
Tamoxifen

Estrogen (ER) positive

69

3 receptors used for breast cancer

Estrogen (ER)
Progesterone (PR)
HER2 gene

70

Receptor status that indicates faster-growing breast cancer but responds better to treatment

HER2

71

Triple positive (ER, PR, and HER2) have _______ outcome

Better

72

Triple negative have _______ survival independent of age, race, stage, and grade
___ times more likely to die and increased risk of local failure because it behaves more aggressively and lacks non-targeted treatments

Worst, 3

73

2 breast cancer staging methods

Clinical
Pathological

74

Physical, operable, gross findings; LNs, breast, etc.

Clinical

75

Microscopic assessment of cell histology

Pathological

76

Breast cancers is a relative ______ disease process; distant mets sometimes occurs _______ after definitive treatment of the primary tumor

Slow, decades

77

3 routes of spread of breast cancer

Extension in breast, ipsilateral breast at risk; tangential treatments skimming beam covers entire breast tissue
Regional LN involvement: axillary, internal mammaries, etc.
Distant mets

78

5 sites of distant mets of breast cancer

LNs most common
Bone
Lung
Liver
Contralateral breast (0.5-1% risk)

79

Best breast cancer treatment method

Multimodality treatment of surgery, RT, and chemo

80

4 breast cancer surgeries

Radical mastectomy
Modified radical mastectomy
Lumpectomy
Breast reconstruction surgery: expanders

81

Remove both breasts, underlining chest pectoralis major and minor muscles, and axillary LNs; high morbidity

Radical mastectomy

82

Remove both breasts and axillary LNs; less morbidity and arm edema and more arm movement

Modified radical mastectomy

83

Remove breast tumor with margins and with axillary dissection or sentinel node biopsy

Lumpectomy

84

Whole body treatment to prevent growth of cancer, adjuvant

Systemic therapy

85

3 types of systemic therapy for breast cancer

Chemo before or after surgery or RT (usually before RT), single or combination
Endocrine therapy/hormonal treatment
HER-2 directed therapy

86

5 breast cancer chemo drugs

Cyclophosphamide
5FU
Methotrexate
Adriamycin/doxorubicin
Vinblastine, mitoxantrone, and mitomycin C

87

2 breast cancer chemo combinations

CMF
AC

88

CMF

Cyclophosphamide
5FU
Methotrexate

89

AC

Doxorubicin
Cyclophosphamide

90

Deprive cancer cells of hormones they thrive on

Endocrine therapy/hormonal treatment

91

2 types of breast cancer endocrine therapy/hormonal treatments

Tamoxifen
Aromatase inhibitors

92

Targets HER-2, stops proliferation, and kills cells; best results with chemo

HER-2 directed therapy
Trastuzumab

93

Interferes with growth of cell

Trastuzumab

94

4 things breast treatment management depends on

Menopausal status
ER positive (better) or negative
Stage
Grade

95

Conservative RT (cure/prevent spread but preserve breast) high volume ___-___ weeks post-op

2-4 weeks

96

Energy range for breast RT

4 (very small breast) - 10 MV (large breast); increases with breast bridge size

97

Limited amount of lung treated during breast cancer RT, have to allow some portion to make sure entire breast is treated but at risk for pneumonitis

1-3.4 cm

98

2 reasons breasts are treated with tangentials

Skims chest wall so small margin of lung in field
Treats entire breast and LN chain

99

Postoperative breast RT in the past and today

Past: used to be prophylactic for LNs and seeding
Today: supraclavicular (SCV) field, IMRT (boost), etc.

100

Why is IMRT justified for the left breast?

Spares dose to heart

101

Why should the arm not be raised too much during breast treatment?

Don't want folds/bolus in infraclavicular area

102

Immobilization device that uses gravity to make the breast fall inferiorly

Slant/inversion boards
Breast ring/cup

103

Pro and con of treating breast in prone position

Pro: pulls breast away from chest wall and lung and makes breast more symmetric, decreasing lung and heart dose and hotspots
Con: harder on older patients and can't be used when treating lymphatics

104

What kind of technique do breast treatments use?

3D isocentric SAD

105

2 things best for split beam breast technique

Asymmetric jaws
MLCs

106

What does the supine position for the breast need to improve dose homogeneity?

Compensating filter (wedge)

107

Initial breast dose with photons and total dose with boost of photons, electrons, or interstitial RT

Initial: 4500-5000 cGy
Total: 6000-6600 cGy

108

Superior breast border at the most cephalad of 5 points

First intercostal space
1-2 cm above superior portion of breast tissue
As far cephalad as possible without including arm
Superior extent of the palpable breast tissue
Over 2 cm cephalad to original location of mass

109

Inferior breast border

1-2 cm caudad to the inframammary fold

110

Medial breast border

At midline of patient as determined by palpation of suprasternal notch and xiphoid process

111

Why is it important to have the border midline during breast treatment?

In case other breast needs to be treated (radiation is cumulative)

112

Lateral breast border

Corresponding to midaxillary line including drain sites or incisions considered at risk, original tumor bed, and appropriate amount of lung margin
Cam be adjusted if more lung needs to be treated

113

Wedge scatter _______ dose to contralateral breast

Increases

114

If not using blocks during breast treatment, have to rotate collimator because of curve of chest wall

Trapezoidal effect

115

Dose _______ at junction point, want _______ dose to scar

Lower, high

116

Half beam blocking with hanging block, jaws at CA, etc. to prevent divergence

Supraclavicular field (SCV)

117

Typically have to _______ to get tangents in straight line and prevent divergence with inferior border of SCV field

Rotate couch

118

_______ and _______ for breast tangents and _______ for SCV

Couch and collimator rotation
Split beam

119

Superior, medial, lateral, and inferior borders for SCV field

Sup: 5 cm to suprasternal notch (SSN), avoid flash if possible to help reduce skin reaction
Med: midpoint of SSN
Lat: about 2-3 cm of the humeral head and block head
Inf: angle of Louis, just above the superior extent of palpable breast tissue, or over 2 cm superior to the original location of the mass in the breast

120

SCV medial and laterals angled ___-___ degrees to decrease exit dose to spinal cord

5-20°

121

Superior, medial, lateral, and inferior borders for posterior axillary boost (PAB) field

Sup: mid to upper clavicle
Med: 1 cm of lung
Lat: about 1-2 cm of humeral head which is blocked
Inf: angle of Louis, just above the superior extent of palpable breast tissue, or over 2 cm superior to the original location of the mass in the breast

122

SCV and PAB dose

5000-5040 cGy

123

Increase midaxillary dose to superior level
Patient flat on table
Special consideration for divergence of beam

Posterior axillary boost (PAB)

124

Small portion of patients have these LNs involved with breast cancer
If tangents deep, need separate field
5° move vertical

Internal mammary

125

Combination photon and electron IMRT breast treatment energy, dose, fractions, number of treatments, and total dose

Photon: 4-6 MV to 1440 cGy at 180 cGy per fraction in 8 treatments
e-: 12-14 MeV fields to 3060 cGy at 180 cGy per fraction in 17 treatments prevents anterior heart dose
Total: 4500 cGy

126

Intact breast initial and boost dose

Initial: 4500 cGy
Boost: 15-1600 cGy

127

Chest wall only (not concerned with cosmesis) initial and boost dose

Initial: 5000 cGy
Boost: 1000 cGy

128

Straight on

En face

129

Only treat involved portion of breast area with 1-2 cm margins in 1-2 weeks

Partial breast irradiation (PBI)

130

3 types of PBI

EBRT most common
Bachy balloon catheter two times a day 6 hours apart
Intraoperative

131

3 breast RT side effects

Telangiectasia
Hyperpigmentation
Fatigue

132

Spidery veins

Telangiectasia

133

Why are pediatric doses lower?

Longer lifespan

134

2 types of pediatric astrocytomas

Low grade
High grade

135

3 reasons RT is used for pediatric brain tumors

Inaccessible tumor
Recurrence
Post-op residue/positive margins

136

Pediatric low grade astrocytoma margin and dose

Margin: 1.5-2 cm around lesion
Dose: 50-55 Gy

137

3 pediatric high grade astrocytomas from least to most aggressive

Anaplastic
Primitive neuroectodermal tumor (PNET)
Glioblastoma multiforme (GBM)

138

6 pediatric brain tumors

Optic gliomas: low grade astrocytomas
Benign tumors of CNS
Medulloblastomas
Ependymomas
Germ cell tumors
Brain stem gliomas

139

25% of childhood brain tumors

Medulloblastomas

140

Pediatric brain tumors that arise from ventricle lining

Ependymomas

141

Tumor of retina most common in 6 months to 4 years old
Chemo

Retinoblastoma

142

Layer at back of eyeball

Retina

143

Retinoblastoma treatment with hanging block for AP and lateral fields for inoperable patients, blocks lens and gives sharp beam edge
Suction cup to displace lobe and spare anterior portion of eye
IMRT to restrict dose

Hanging block technique

144

Retinoblastoma dose and dose per fraction

40-50 Gy at 180-200 cGy per fraction

145

Iodine-125 eye plaque stitched in eye dose in one week and cure

Dose: 30-40 Gy
Over 80% cure

146

Small round blue cells from neural crest, most common extracranial cancer in infancy
Most common site: adrenals of fetus, chest, pelvis, neck, etc.
Patients usually newborns to 24 months, median age of diagnosis = 17 months
Very aggressive and poor survival
Can be cured by surgery alone if caught early

Neuroblastoma

147

Group of embryonic cells during formation of neural tube

Neural crest

148

2 sites of neuroblastoma mets

Abdomen
Liver

149

Neuroblastoma dose to tumor bed post-op and -chemo and palliative dose

Dose: 20-30 Gy
Palliative: 1000 cGy

150

Newborns can receive about _____ cGy without problems

500 cGy

151

What is a side effect of neuroblastoma RT?

Bone and soft tissue decreased growth

152

Malignant embryonic cancer of kidney

Wilms' tumor

153

Average age of wilms' tumor presentation

3-4 years old

154

Wilms tumor dose to positive margin and dose to large tumors that rupture and spill into abdominal cavity

Pos: 20 Gy
Rupture: 3000 cGy to whole abdomen (great side effects)

155

3 risks when treating wilms' tumor with RT

Scoliosis
Soft tissue atrophy
Bone growth defects

156

Main treatment of wilms' tumor

Nephrectomy of affected kidney

157

Arise in mesenchyme anywhere in body

Soft tissue sarcoma (STS)

158

Connective tissue

Mesenchyme

159

Pediatric soft tissue sarcoma margin and dose

Margin: 1 cm
Dose: 36-5040 cGy

160

About 40% of pediatric STS's; arise in H&N, genitourinary region, extremities, and truck
75% occur before age of 10
Amputation and pelvic exenteration

Rhabdomyosarcomas

161

2 rhabdomyosarcoma sites that have better prognosis and 1 that has worst prognosis

Better: orbit and genitourinary
Worst: alveolar (extremities and trunk)

162

Pediatric germ cell tumor dose

20-25 Gy

163

Usually fatal pediatric tumor; surgery treatment of chouce

Liver tumor

164

Most common childhood cancer overall
TBI and possible CNS prophylactic treatments

Acute lymphoblastic leukemia (ALL)

165

Pediatric disease of immune system that can cause lytic lesions

Langerhans cell histiocytosis (histiocytosis X syndromes)

166

Involved field pediatric hodgkin's dose after chemo to reduce recurrence

1500-2500 cGy

167

Childhood tumor commonly developed in males

Nasopharynx

168

Childhood nasopharynx tumor dose that helps control relapse and positive margins

3000 cGy

169

Overgrowth of scar tissue more common in young women and African Americans; sharp pain, itchiness, and poor cosmesis

Keloids

170

Keloid dose

900-1200 cGy in 3 fractions 24-48 hours post-op