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Flashcards in Test 4 Deck (170)
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1
Q

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.

A

Prostate cancer

2
Q

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

A

65

3
Q

3 types of prostate RT

A

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

4
Q

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

A

Maximal androgen blockade (MAB)

5
Q

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

A

Hormonal castration

6
Q

4 things prostate treatment depends on

A

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

7
Q

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

A

Gleason score (GS)

8
Q

Lateral and posterior borders for prostate cancer

A

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

9
Q

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

A

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
Q

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

A

4, 6-7

11
Q

Less than 35-40% of rectum receiving ___ Gy

A

60 Gy

12
Q

Seminal vesicles _______ and _______ to prostate

A

Superior, posterior

13
Q

Prostate ___ cm above urethra

A

1 cm

14
Q

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

A

6 mm
9 mm
1.5 cm

15
Q

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

A

76 Gy

200 cGy

16
Q

Early stage six field prostate and SV dose and total dose

A

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

17
Q

Prostate dose
LN involvement
Four field pelvis

A

4500 cGy

18
Q

Prostate dose
LN involvement
Six field prostate and SV

A

5940 cGy

19
Q

Prostate dose
LN involvement
Six field prostate only total

A

7200-7400 cGy

20
Q

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

A

8440 cGy at 200 cGy per fraction

21
Q

Why are the prostate clinical trials effective?

A

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

22
Q

2 forms of daily IGRT for prostate treatment

A

US not as common: sonory or iBeam

Gold fiducials

23
Q

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

A

Gold fiducials

24
Q

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

A

Optimization

25
Q

If DVH tails off = _______

A

Hotspots

26
Q

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

A

Y-axis

27
Q

Normal fractionated dose

A

180-200 cGy

28
Q

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

A

1-2 hours
Perineal
1-2

29
Q

3 radioactive isotopes used in prostate treatments

A

Iodine-125
Palladium
Iridium

30
Q

Palladium half-life and energy

A

T1/2: 17 days

E: 21 keV

31
Q

Iodine-125 half-life and energy

A

T1/2: 59.6 days

E: 28 keV

32
Q

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

A

180-200 seeds
125 cGy
145-160 cGy

33
Q

Which prostate seed source gets higher dose?

A

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

34
Q

Which prostate seed source is used in larger volume implant?

A

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

35
Q

Iodine-125 typical dose, rate, and size

A

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

36
Q

Palladium dose and rate

A

125 cGy, 19 cGy/hr

37
Q

4 bladder cancer treatments

A

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

38
Q

Chemo instilled directly in bladder

A

Intravesical chemo

39
Q

What is an example of intravesical chemo?

A

Bacillus calmette-guerin (BCG)

40
Q

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

A

30 Gy, 2 weeks

41
Q

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

A

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

42
Q

2 reasons the bladder is treated empty

A

Guarantee size

Smaller treatment field

43
Q

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

A

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

44
Q

Lateral bladder fields anterior and posterior borders

A

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

45
Q

Helps reduce penis/urethra cancer in foreskin

A

Circumsicion

46
Q

Penis/urethra cancer position

A

Opposed laterals in prone

47
Q

Penis/urethra cancer initial, boost, and total dose

A

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

48
Q

5 LNs associated with penis cancer

A
External iliacs
Obturator
Presacral
Inguinal
Pelvic
49
Q

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

A

No: 50 Gy
Palpable: 70 Gy

50
Q

Treatment of choice and treatment for inoperable kidney cancer

A

Choice: surgery
Inoperable: RT

51
Q

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

A

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

52
Q

Kidney cancer energy because there’s a lot of tissue

A

10 MV or more

53
Q

Kidney cancer fields

A

Equal or unevenly weighted fields

AP/PA and obliques

54
Q

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

A

Under 15-18 Gy

55
Q

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

A

Hypertension

56
Q

3 structures kidney and ureter involvement treatment portals include

A

Entire renal fossa
Ureteral bed
Ipsilateral bladder trigone

57
Q

Seminomas of the testis are considered _______

A

Radiosensitive

58
Q

3 LNs associated with early seminomas of the testis

A

Periaortic
Ipsilateral renal hilar
Ipsilateral iliacs

59
Q

Unilateral and bilateral testicular treatment field

A

Uni: hockey stick
Bi: inverted-Y

60
Q

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

A

10%

61
Q

Initial dose, fractions, and boost for larger testicular masses

A

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

62
Q

Length and lateral border for testicular seminoma cancer

A

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
Q

Left sided testicular tumor field

A

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

64
Q

5 breast cancer prognostic factors

A

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
Q

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

A

Axillary LN dissection

66
Q

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

A

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

67
Q

3 breast cancer histologies

A

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

68
Q

Receptor status most common in postmenopausal women, slow growing
Tamoxifen

A

Estrogen (ER) positive

69
Q

3 receptors used for breast cancer

A

Estrogen (ER)
Progesterone (PR)
HER2 gene

70
Q

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

A

HER2

71
Q

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

A

Better

72
Q

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

A

Worst, 3

73
Q

2 breast cancer staging methods

A

Clinical

Pathological

74
Q

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

A

Clinical

75
Q

Microscopic assessment of cell histology

A

Pathological

76
Q

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

A

Slow, decades

77
Q

3 routes of spread of breast cancer

A

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
Q

5 sites of distant mets of breast cancer

A
LNs most common
Bone
Lung
Liver
Contralateral breast (0.5-1% risk)
79
Q

Best breast cancer treatment method

A

Multimodality treatment of surgery, RT, and chemo

80
Q

4 breast cancer surgeries

A

Radical mastectomy
Modified radical mastectomy
Lumpectomy
Breast reconstruction surgery: expanders

81
Q

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

A

Radical mastectomy

82
Q

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

A

Modified radical mastectomy

83
Q

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

A

Lumpectomy

84
Q

Whole body treatment to prevent growth of cancer, adjuvant

A

Systemic therapy

85
Q

3 types of systemic therapy for breast cancer

A

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

86
Q

5 breast cancer chemo drugs

A
Cyclophosphamide
5FU
Methotrexate
Adriamycin/doxorubicin
Vinblastine, mitoxantrone, and mitomycin C
87
Q

2 breast cancer chemo combinations

A

CMF

AC

88
Q

CMF

A

Cyclophosphamide
5FU
Methotrexate

89
Q

AC

A

Doxorubicin

Cyclophosphamide

90
Q

Deprive cancer cells of hormones they thrive on

A

Endocrine therapy/hormonal treatment

91
Q

2 types of breast cancer endocrine therapy/hormonal treatments

A

Tamoxifen

Aromatase inhibitors

92
Q

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

A

HER-2 directed therapy

Trastuzumab

93
Q

Interferes with growth of cell

A

Trastuzumab

94
Q

4 things breast treatment management depends on

A

Menopausal status
ER positive (better) or negative
Stage
Grade

95
Q

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

A

2-4 weeks

96
Q

Energy range for breast RT

A

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

97
Q

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

A

1-3.4 cm

98
Q

2 reasons breasts are treated with tangentials

A

Skims chest wall so small margin of lung in field

Treats entire breast and LN chain

99
Q

Postoperative breast RT in the past and today

A

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

100
Q

Why is IMRT justified for the left breast?

A

Spares dose to heart

101
Q

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

A

Don’t want folds/bolus in infraclavicular area

102
Q

Immobilization device that uses gravity to make the breast fall inferiorly

A

Slant/inversion boards

Breast ring/cup

103
Q

Pro and con of treating breast in prone position

A

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
Q

What kind of technique do breast treatments use?

A

3D isocentric SAD

105
Q

2 things best for split beam breast technique

A

Asymmetric jaws

MLCs

106
Q

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

A

Compensating filter (wedge)

107
Q

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

A

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

108
Q

Superior breast border at the most cephalad of 5 points

A

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
Q

Inferior breast border

A

1-2 cm caudad to the inframammary fold

110
Q

Medial breast border

A

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

111
Q

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

A

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

112
Q

Lateral breast border

A

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
Q

Wedge scatter _______ dose to contralateral breast

A

Increases

114
Q

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

A

Trapezoidal effect

115
Q

Dose _______ at junction point, want _______ dose to scar

A

Lower, high

116
Q

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

A

Supraclavicular field (SCV)

117
Q

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

A

Rotate couch

118
Q

_______ and _______ for breast tangents and _______ for SCV

A

Couch and collimator rotation

Split beam

119
Q

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

A

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
Q

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

A

5-20°

121
Q

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

A

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
Q

SCV and PAB dose

A

5000-5040 cGy

123
Q

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

A

Posterior axillary boost (PAB)

124
Q

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

A

Internal mammary

125
Q

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

A

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
Q

Intact breast initial and boost dose

A

Initial: 4500 cGy
Boost: 15-1600 cGy

127
Q

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

A

Initial: 5000 cGy
Boost: 1000 cGy

128
Q

Straight on

A

En face

129
Q

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

A

Partial breast irradiation (PBI)

130
Q

3 types of PBI

A

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

131
Q

3 breast RT side effects

A

Telangiectasia
Hyperpigmentation
Fatigue

132
Q

Spidery veins

A

Telangiectasia

133
Q

Why are pediatric doses lower?

A

Longer lifespan

134
Q

2 types of pediatric astrocytomas

A

Low grade

High grade

135
Q

3 reasons RT is used for pediatric brain tumors

A

Inaccessible tumor
Recurrence
Post-op residue/positive margins

136
Q

Pediatric low grade astrocytoma margin and dose

A

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

137
Q

3 pediatric high grade astrocytomas from least to most aggressive

A

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

138
Q

6 pediatric brain tumors

A
Optic gliomas: low grade astrocytomas
Benign tumors of CNS
Medulloblastomas
Ependymomas
Germ cell tumors
Brain stem gliomas
139
Q

25% of childhood brain tumors

A

Medulloblastomas

140
Q

Pediatric brain tumors that arise from ventricle lining

A

Ependymomas

141
Q

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

Chemo

A

Retinoblastoma

142
Q

Layer at back of eyeball

A

Retina

143
Q

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

A

Hanging block technique

144
Q

Retinoblastoma dose and dose per fraction

A

40-50 Gy at 180-200 cGy per fraction

145
Q

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

A

Dose: 30-40 Gy

Over 80% cure

146
Q

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

A

Neuroblastoma

147
Q

Group of embryonic cells during formation of neural tube

A

Neural crest

148
Q

2 sites of neuroblastoma mets

A

Abdomen

Liver

149
Q

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

A

Dose: 20-30 Gy
Palliative: 1000 cGy

150
Q

Newborns can receive about _____ cGy without problems

A

500 cGy

151
Q

What is a side effect of neuroblastoma RT?

A

Bone and soft tissue decreased growth

152
Q

Malignant embryonic cancer of kidney

A

Wilms’ tumor

153
Q

Average age of wilms’ tumor presentation

A

3-4 years old

154
Q

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

A

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

155
Q

3 risks when treating wilms’ tumor with RT

A

Scoliosis
Soft tissue atrophy
Bone growth defects

156
Q

Main treatment of wilms’ tumor

A

Nephrectomy of affected kidney

157
Q

Arise in mesenchyme anywhere in body

A

Soft tissue sarcoma (STS)

158
Q

Connective tissue

A

Mesenchyme

159
Q

Pediatric soft tissue sarcoma margin and dose

A

Margin: 1 cm
Dose: 36-5040 cGy

160
Q

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

A

Rhabdomyosarcomas

161
Q

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

A

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

162
Q

Pediatric germ cell tumor dose

A

20-25 Gy

163
Q

Usually fatal pediatric tumor; surgery treatment of chouce

A

Liver tumor

164
Q

Most common childhood cancer overall

TBI and possible CNS prophylactic treatments

A

Acute lymphoblastic leukemia (ALL)

165
Q

Pediatric disease of immune system that can cause lytic lesions

A

Langerhans cell histiocytosis (histiocytosis X syndromes)

166
Q

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

A

1500-2500 cGy

167
Q

Childhood tumor commonly developed in males

A

Nasopharynx

168
Q

Childhood nasopharynx tumor dose that helps control relapse and positive margins

A

3000 cGy

169
Q

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

A

Keloids

170
Q

Keloid dose

A

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