Oncology (1-6) Flashcards

1
Q

a group of cells whose proliferation is uncontrolled and, under certain circumstances, can metastasis to distant sites

A

cancer

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2
Q

what is the dominant type of cancer in cats

A

FeLV infection

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3
Q

name the 7 alterations in cellular physiology that collectively dictate malignant growth

A
  1. a self sufficiency in growth
  2. an insensitivity to anti-growth signals
  3. an ability to evade programmed death (apoptosis)
  4. limitless replicative potential (mainly through reactivation of telomerase)
  5. an ability to sustain angiogenesis
  6. an ability to invade and metastasize
  7. an ability to evade host immunity
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4
Q

name 4 mechanisms of oncogene activation

A
  1. chromosomal translocation
  2. gene amplification
  3. point mutations
  4. viral insertions
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5
Q

cause a stimulatory effect on cell growth and proliferation; produce positive signals leading to uncontrolled growth

A

oncogene

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6
Q

cause tumor formation as a result from loss of inhibitory functions; has an inhibitory effect on cell growth and proliferation

A

tumor suppressor genes

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7
Q

name 3 treatment modalities of cancer

A
  1. surgery
  2. radiotherapy
  3. chemotherapy
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8
Q

this is the most important treatment modality of cancer; majority can be treated this way

A

surgery

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9
Q

this treatment modality of cancer is very important for primary tumors

A

radiotherapy

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10
Q

this is a systemic treatment important for secondary disease and ‘liquid tumors’ like leukemia

A

chemotherapy

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11
Q

this describes the severity of a patient’s cancer based on size and/or extent (reach) of the original (primary) tumor and whether or not cancer has spread in the body

A

staging

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12
Q

name 3 reasons why staging in cancer is important

A
  1. helps plan appropriate treatment
  2. can be used to determine prognosis
  3. helps vets and researchers exchange info about the patients
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13
Q

name 5 common elements considered in most cancer staging systems

A
  1. site of primary tumor and cell type
  2. tumor size and extent (reach)
  3. presence of metastasis
  4. tumor grade
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14
Q

what is the TNM staging system based on

A

T ‐ size and invasiveness of tumor
N ‐ status of nodal metastasis
M ‐ status of distant metastasis

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15
Q

this stage of cancer means the carcinoma is in situ

A

stage 0

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16
Q

this stage of cancer means the cancer has spread to distant tissues or organs

A

stage IV

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17
Q

this is a means of detecting disease early in asymptomatic individuals

A

screening

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18
Q

name 4 types of tumors diagnostic imaging is required for

A
  1. deep tumors
  2. tumors involving vital structures
  3. tumors involving bones
  4. tumors adjacent to bone
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19
Q

this type of imaging is useful for assessing parenchymatous organs and internal lymph nodes

A

ultrasound

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20
Q

this type of imaging is great for bony lesions, pulmonary lesions, and radiation planning

A

CT

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21
Q

this type of imaging is best for CNS lesions; many more shades of grey in soft tissue

A

MRI

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22
Q

name the type of biopsy

used to remove small cores of tumor tissue from solid lesions

A

tru-cut biopsy

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23
Q

name the type of biopsy

excellent for skin and superficial soft-tissue tumors; recover substantially more tissue than needle aspirates

A

skin punch biopsy

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24
Q

name the type of biopsy

surgical removal of a solid piece of tissue from a tumor for histopathological examination

A

incisional biopsy

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25
Q

name the type of biopsy

complete surgical extirpation of a tumor following which tissue samples are removed for histopathological examination

A

excisional biopsy

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26
Q

name the type of biopsy

often indicated in the diagnosis of conditions affecting lymphoid and myeloid systems - may take form of an aspirate or a core biopsy

A

bone marrow biopsy

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27
Q

name 3 possible sites for bone marrow biopsy

A
  1. humerus
  2. femur
  3. iliac crest
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28
Q

this is defined as one or more clinical signs induced by a tumor distant from its primary site; often due to production of a hormone, cytokine, enzyme/peptide, or homone-like substance

A

paraneoplastic syndrome (PNS)

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29
Q

what are the 2 ways factors causing PNS can be secreted?

A
  1. othotopically / topically
  2. ectopically
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30
Q

what 3 forms of calcium are included in the total serum calcium?

A
  1. active ionized calcium
  2. inactive protein-bound calcium
  3. complexed calcium
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31
Q

low albumin will have what effect on total calcium

A

reduce total calcium

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32
Q

high albumin will have what effect on total calcim

A

increase total calcium

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33
Q

what 3 things is calcium homeostasis tightly regulated by

A
  1. parathyroid hormone (PTH)
  2. active vitamin D (calcitriol)
  3. calcitonin
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34
Q

what is the most common cause of hypercalcemia in the dog?

A

cancer

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35
Q

what are the most common initial signs of hypercalcemia

A

primary polyuria with secondary polydipsia

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36
Q

name 4 tumors associated with hypercalcemia of malignancy

A
  1. lymphoproliferatice disease
  2. apocrine gland neoplasia
  3. parathyroid gland neoplasia
  4. other carcinomas
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37
Q

list the 8 investigations that should be made to diagnose hypercalcemia of malignancy

A
  1. clinical exam (lymph nodes, rectal)
  2. hematology/chemistry/UA
  3. ionized calcium
  4. radiography
  5. U/S
  6. FNA/biopsy abnormalities
  7. PTH/PTHrP
  8. bone marrow biopsy
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38
Q

name 5 differential diagnoses for hypercalcemia

A
  1. malignancy
  2. primary hyperparathyroidism
  3. primary renal disease
  4. hypervitaminosis D
  5. hyperthyroidism
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39
Q

what happens to PTH when there is hypercalcemia?

(except in cases of primary hyperparathyroidism)

A

reduced

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40
Q

what is the treatment for patients midly affected by hypercalcemia

A

2-3x maintenance IV isotonic fluid

(for subclinical dehydration)

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41
Q

what is the treatment for patients moderately affected by hypercalcemia

A

loop diuretics

(for non-azotemic patients)

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42
Q

what is the treatment for patients severely affected by hypercalcemia

A

salmon calcitonin

(oncologic emergency)

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43
Q

these are commonly co-administered with calcitonin because their peak effect can be delayed for a few days after administration but persists for weeks;
ideal for management of chronic hypercalcemia

A

biophosphonates

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44
Q

what are the clinical signs of hypoglycemia

A

neurological sgns and catecholamine effects

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45
Q

name 6 differential diagnoses of hypoglycemia

A
  1. neonatal
  2. breed-related
  3. sepsis
  4. liver failure
  5. insulinoma
  6. other paraneoplastic
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46
Q

list the 6 investigations that should be made to diagnose paraneoplastic hypocalcemia

A
  1. history
  2. physical exam
  3. biochemistry/hematology
  4. diagnositc imaging
  5. advanced imaging (CT/MRI)
  6. serum insulin
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47
Q

what is the treatment of choice for hypocalcemia caused by insulinoma

A

surgery

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48
Q

what is hyperhistaminemia (can be caused by mast cell tumors) treated with

A
  1. diphenhydramine, loratadine (H1 receptor blockade)
  2. ranitide, cimetidine or famotidine (H2 receptor blockade)
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49
Q

this is acquired due to an immune response against acetylcholine receptors of the motor nerve end-plates in skeletal muscle;
commonest PNS (paraneoplastic syndrome) in cats and dogs with thymoma

A

myasthenia gravis

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50
Q

this paraneoplastic syndrome (PNS) is associated with phaeochromacytoma (tumor of the adrenal medulla), secreting catecholamines

A

hypertension

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51
Q

what can hyperviscosity be associated with

A
  1. increased plasma proteins
  2. increased cell numbers (WBCs or RBCs)
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52
Q

name 5 clinical signs of hyperviscosity

A
  1. CNS
  2. polyuria/polydipsia
  3. cardiac compromise
  4. hemorrhage
  5. ocular changes
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53
Q

this is a syndrome characterized by periosteal proliferation of new bone

A

hypertrophic osteopathy

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54
Q

what type of tumor is hypertrophic osteopathy associated with

A

thoracic neoplasia
(or other space occupying lesions in chest/abdomen)

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55
Q

name some risks of oncology surgery

A
  1. non-diagnostic sample
  2. seeding
  3. incr. contamination field
  4. infection
  5. wound breakdown
  6. hemorrhage
  7. pain
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56
Q

what is the surgical dose for oncology surgery?

A
  1. remove adequate margin of tissue around tumor gross edge
  2. preserve as much healthy tissue as possible
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57
Q

what is the general rule for numerical margins for a mast cell tumor

A

2 cm

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58
Q

what is the general rule for numerical margins for STS

A

3-5 cm

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59
Q

what is the general rule for numerical margins for a melanoma

A

2-3 cm

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60
Q

what is the general rule for numerical margins for a carcioma

A

1-2 cm

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61
Q

name the 6 basic principles of surgical oncology - involving removing the tumor without seeding/spreading

A
  1. plan resection
  2. look but don’t touch
  3. protect wound from seeding
  4. ensure wound heals as planned
  5. orientate the scar
  6. extirpate the nodes?
62
Q

what are the 4 options for closure following tumor removal

A
  1. primary, local closure
  2. local flaps
  3. axial pattern flaps
  4. free skin grafts
63
Q

name 4 important roles that make up a surgical oncology team

A
  1. carer
  2. oncologist
  3. nurse
  4. anaesthesia team
64
Q

name 4 ways oncology surgery can be classified

A
  1. debulking
  2. marginal
  3. wide
  4. radical
65
Q

name the oncology surgery classification

definition is variable and may result in remaining macroscopic or microscopic disease;
piecemeal and intrascapular removal is classified as this;
this type of surge ymay improce patient function/comfort but where macroscopic disease remains the efficacy of subsequent adjuvant therapy may be reduced

A

debulking

66
Q

name the oncology surgery classification

removal of tissue just peripheral to the gross mass, excising narrow ‘piece’ of normal tissue;
may be all that is required with benign lesions; microscopic neoplasia may remain with malignancies

A

marginal

67
Q

name the oncology surgery classification

curative intent surgery and incorporates a prescribed margin of normal tissue

A

wide

68
Q

name the oncology surgery classification

curative intent surgery removes the entire body compartment which contains the tumor

A

radical

69
Q

how should lateral (numerical) margins be measured

A

using a ruler

70
Q

name some considerations when decision-making for surgical margins

A
  1. tumor type
  2. tumor site
  3. metastases
  4. co-morbidities
  5. owner preference
  6. availability of neo-adjuvant or adjuvant therapies
71
Q

once surgery is complete, what should be done to all cut margins on the excised mass before sending to pathology

A

all cut margins should be inked

72
Q

what are the 3 best colors for inking cut margins on excised masses for pathology

A

yellow, blue, green

73
Q

what do most chemotherapy or “cytotoxic” drugs act upon
(which provides some specificity/sparing of normal cells)

A

cell division

74
Q

what kind of tumor cells are generally resistant to chemotherapy and act as a reservoir to repopulate tumors

A

non-dividing cells (G0)

75
Q
A
76
Q

this is the time taken for a tumor to physically double in size; much shorter during early tumor growth

A

Mass Doubling Time (MDT)

77
Q

name three factors affecting Mass Doubling Time (MDT) of tumors

A
  1. proportion of total cells which are actively dividing
  2. duration of cell cycle
  3. number of cells being lost by cell death
78
Q

this is the proportion of total cells which are actively dividing

A

growth fraction (GF)

79
Q

name 6 factors affecting tumor response to chemotherapy

A
  1. growth raction and mass doubling time
  2. inherent tumor cell sensitivity
  3. inherent or acquired drug resistance
  4. drug dosage
  5. tumor cell heterogeneity
  6. tumor blood supply
80
Q

name 8 basic mechanisms by which drug resistance occurs

A
  1. less drug entering cell (binding and uptake)
  2. defective drug activation
  3. increased drug inactivation
  4. increased target molecules
  5. altered target molecules
  6. enhanced DNA repair
  7. inability to undergo apoptosis
  8. enhanced export of drug from the cells
81
Q

what does the tumor cell kill hypothesis state?

A

cytotoxic drugs kill tumor cells according to first order kinetics

82
Q

what inaccurate assumption does the Tumor Cell Kill Hypothesis make to help us understand responses

A

tumor is homogenous in terms of chemosensitivity

83
Q

for most cytotoxic drugs, what is the dose based on

A

body surface area (BSA) of the patient

84
Q

what is the equation for BSA (body surface area)

A

surface area (m^2) = (k x body weight)^0.66 / 10^4

k = 10.1 (dogs), 10 (cats)

85
Q

what are the 2 most common dose limiting toxicities of chemotherapy drugs

A
  1. myelosuppression
  2. GI side effects
86
Q

what is a chemotherapy dose schedule

A

chemotherapy administered at intervals during which normal tissues recover fully but tumor does not

87
Q

what three ways can chemotherapy be used

A
  1. sole treatment for highly chemosensitive tumors
  2. post-operatively
  3. neo-adjunctively prior to surgery
88
Q

what are the 6 main categories of chemotherapy agents based on their mechanisms of action

A
  1. alkylating agents
  2. mitotic spindle inhibitors/toxins
  3. antimetabolites
  4. antitumor antibiotic
  5. glucocorticoids
  6. miscellaneous
89
Q

name the chemotherapy agent category

cause cross-linking and breaking of DNA molecules, interfering with DNA replication and RNA transcription

(cyclophosphamide, chlorambucil, melphalan, lomustine)

A

alkylating agents

90
Q

name the chemotherapy agent category

bind to cytoplasmic microtubular proteins and arrest mitosis in metaphase

(vincristine, vinblastine, vinorelbine, paclitaxel)

A

Mitotic spindle inhibitors/toxins

91
Q

name the chemotherapy agent category

mimic normal substrates for nucleic acid synthesis; inhibit cellular enzymes or cause production of non-functional molecules

(methotrexate and cytosine arabinoside)

A

antimetabolites

92
Q

name the chemotherapy agent category

bind to DNA and inhibit DNA and RNA synthesis through various mechanisms

(doxorubicin, epirubicin, mitoxantrone)

A

antitumor antibiotics

93
Q

name the chemotherapy agent category

cytolytic for lymphoid tissues and therefore useful in treatment of lymphoproliferative diseases;
mechanism of action unclear

A

glucocorticoids

94
Q

are alkylating agents cell cycle specific?

A

no, non-specific

95
Q

are anti-tumor antibiotics cell cycle specific?

A

no, but more active in S phase

96
Q

are antimetabolites cell cycle specific?

A

yes, S phase specific

97
Q

what is the major drug in glucocorticoid class of chemotherapy agents

A

prednisolone

98
Q

are mitotic spindle inhibitors (vinca alkaloids) cell cycle specific?

A

yes, M phase specific

99
Q

name 5 drug toxicities that can occur with chemotherapy delivery

A
  1. GI adverse effects
  2. myelosuppression
  3. anaphylaxis
  4. drug extravasation
  5. specific adverse effects
100
Q

how to manage anaphylaxis as a side effect of chemotherapy

A

premedication with antihistamines

101
Q

how to manage cardiac dysrhythmias as a side effect of chemotherapy

A

stop infusion then restart at reduced rate

102
Q

drug that causes soft tissue damage following inadvertant perivascular administration;
self-limiting inflammation, erythema, discomfort
ex: vinca alkaloids

A

irritant

103
Q

drug that causes soft tissue damage following inadvertant perivascular administration;
catastrophic progressive soft tissue necrosis
ex: doxorubicin

A

vesicant

104
Q

how to manage drug extravasation as a side effect of chemotherapy

A

stop drug administration immediately and attempt to withdraw as much drug as possible through the cannula in place

105
Q

how to treat drug extravasation of vincristine (irritant)

A

HOT compress;
hyaluronidase diluted with 0.9% saline

106
Q

how to treat drug extravasation of doxorubicin/epirubicin (vesicants)

A

COLD compress;
hyaluronidase diluted with 0.9% saline

107
Q

this side effect of chemotherapy is the killing of rapidly dividing bone marrow stem cells

A

myelosuppression

108
Q

how to manage febrile neutropenia (myelosupression) as a side effect of chemotherapy

A

assume patient is septic! hospitilize, broad spectrum IV antibiotics, etc

109
Q

how to manage asymptomatic neutropenic patients (myelosuppression) as a side effect of chemotherapy

A

chemotherapy dose ddelat and reduction

110
Q

name 4 specific adverse effects (related to specific chemotherapeutic agents)

A
  1. cardiotoxicity
  2. sterile hemorrhagic cystitis
  3. nephrotoxicity
  4. hepatotoxicity
111
Q

this is a low dose oral form of chemotherapy which targets angiogenesis;
usually low dose cyclophosphamide + prioxicam or meloxicam

A

metronomic chemotherapy

112
Q

name 6 receptor tyrosine kinases (RTKs) which can be dysregulated in cancer

A
  1. FGFR (fibroblast growth factor receptor)
  2. VEGFR (vascular endothelial)
  3. PDGFR (platelet derived)
  4. EGFR (epidermal)
  5. MET (hepatocyte GFR)
  6. KIT (hematopoietic GFR)
113
Q

name the two tyrosine kinase inhibitors (TKIs) that have been approved in veterinary medicine for treatment of mast cell tumors

A

toceranib & masitinib

114
Q

this is a key treatment modality for cancer that is based on the use of high energy rays to kill neoplastic cells

A

radiation therapy (RT)

115
Q

how is radiotherapy prescribed? (what units?)

A

Gray (J/kg)

116
Q

this is when the total dose is divided into multiple smaller doses over the course of several days to weeks (common with radiotherapy)

A

fractionation

117
Q

this is the amount of energy (radiation) absorbed by the patient (tissue); unit used in radiation therapy treatment

A

Gray (J/kg)

118
Q

this is the particular dose and number of fractions to be given to a particular tumor (radiotherapy)

A

RT protocol

119
Q

what is the rationale behind fractionation of radiotherapy

A
  1. helps normal tissues tolerate treatment better
  2. potentiates efficiency
120
Q

this type of radiation toxicity typically develops during or just after treatment

A

early (acute) toxicity

121
Q

how long after completion of treatment are acute toxicities from radiotherapy expected to resolve

A

1-4 weeks

122
Q

what tissues do early toxicities from radiotherapy affect

A

rapidly proliferating tissues (skin and mucus membranes)

123
Q

what do early toxicities from radiotherapy depend on

A

dose intensity & total dose

124
Q

name 5 things that should be considered when managing a patient with acute radiation induced toxicities

A
  1. manage discomfort
  2. protect from external damage
  3. keep site clean (but do not rub or cover)
  4. do not use prophylactic antibiotics
  5. consider topical ointments/medications
125
Q

this type of radiation toxicity typically occurs months-years after RT

A

late (chronic) toxicity

126
Q

what tissues does late toxicity from radiotherapy damage

A

with low turn-over rates (connective tissue or neuronal tissue)

127
Q

what increases the risk of late toxicity from radiotherapy

A

larger dose per fraction

128
Q

this refers to protocols that use a higher number of fractions (10-20) using a relatively low dose per fraction & a high total dose; often administered on a daily basis

A

definitive/curative intent protocols

129
Q

name 3 advantages of definitive intent protocols for radiotherapy

A
  1. improves therapeutic index
  2. optimizes chance of long term tumor control
  3. risks of late toxicities low
130
Q

name 2 disadvantages of definitive intent protocols for radiotherapy

A
  1. more demanding (vet visits, cost, etc)
  2. higher risk of acute toxicities
131
Q

these protocols consist of 3-6 fractions typically 1-2 times weekly for 3-4 weeks OR daily for 1 week;
higher dose per fraction & lower total dose
aim is to quality of life in dog with advanced cancer

A

palliative protocols

132
Q

name 1 disadvantage of palliative protocols for radiotherapy

A
  1. risk of late toxicity
133
Q

name 2 advantages of palliative protocols for radiotherapy

A
  1. less acute toxicities seen
  2. lower cost (fewer vet visits)
134
Q

these protocols consist of very few treatments (1-3 fractions) given within a few days (1-5);
high dose intensity & high dose fraction;
used for well delineated, non-infiltrative and small tumors

A

stereotactic protocols

135
Q

name 1 advantage of sterotactic protocols for radiotherapy

A

good tumor control rate with fewer treatments

136
Q

name 1 disadvantage of sterotactic protocols for radiotherapy

A

risk of late complications

137
Q

name 3 indications of radiotherapy in veterinary oncology

A
  1. sole therapy
  2. in combination with surgery
  3. benign conditions
138
Q

this is the most common form of administering radiation to dogs and cats;
source of radiation is at distance from body of patient;
ionizing radiation can be human made or obtained from natural decay

A

teleradiotherapy (external beam radiotherapy)

139
Q

this is voltage in the. range of 100-500kV (x-rays);
best for superficial/shallow tumors (<2-3cm)

A

orthovoltage (kV)

140
Q

name 3 disadvantages of orhtovoltage (kV) for radiotherapy

A
  1. low penetration
  2. higher bone absorption
  3. limited small field size
141
Q

this is voltage over 1 million volts (x-rays or gamma rays)

A

Megavoltage (MV)

142
Q

name 3 advantages of megavoltage for radiotherapy

A
  1. high penetration
  2. homogenous tissue absorption
  3. large field size
143
Q

these rays are from radioactive decay;
decay of cobalt 60

A

gamma rays

144
Q

these rays are man-made;
electrons are produced by heating the filament (cathode, C), then accelerated in a straight line in accelerating waveguide; Electrons strike a target (anode, A) to produce these high-energy rays

A

x-rays

145
Q

this is a form of radiotherapy in which the source of radiation is applied in or on the patient in one prolonged dose, using surface applicators, needles or seeds

A

Brachytherapy

146
Q

name 3 advantages of brachytherapy

A
  1. deliver continuous radiation
  2. minimizes dose to surrounding tissue
  3. maximizes dose to tumor
147
Q

this is a form of brachytherapy where the source is applied to the surface of the lesion;
only for superficial lesions (2-3mm)

A

plesiotherapy

148
Q

this is when radiation is targeted to a specific tissue by using a radionuclide;
routes of administration are oral, IV, and intraperitoneal

A

systemic radiation

149
Q

name the type of ionization

a secondary electron resulting from absorption of an x-ray interacts with the DNA to produce an effect (damage)

A

direct ionization

150
Q

name the type of ionization

secondary electron interacts with water molecules to produce a hydroxyl radical which produces damage to DNA;
oxygen is needed to then attach to damaged ends of DNA so that DNA cannot repair

A

indirect action/ionization

151
Q
A