Radiation Therapy Flashcards
Term used for individual administration of dose of radiation
Fraction
____ toxicity -> Fraction size
____ toxicity -> Total dose
Late toxicity -> Fraction size
Acute toxicity -> Total dose
Type of radiation therapy that has penetration = 3mm and good for small, superficial tumors
Strontium Therapy (Plesiotherapy)
Radiation Biology Mechanism (4 Steps)
1) Radiation interaction with tissue
2) Free radical formation
3) DNA damage
4) Cell death, permanent DNA alteration
Goal of Definitive radiation therapy
Goal is to limit late toxicity
General margin of ____ cm around the visible tumor or scar to treat microscopic disease
1-2 cm
Term used for amount of radiation absorbed by the patient
Dose
What is the most commonly used external beam radiation therapy?
3D-Conformal Radiation Therapy
CKD dogs have average survival of ____year(s), depending on stage and owner commitment
1-1.5 years
This type of radiation therapy has higher risk of clincally significant late toxicity
Coarse-Fraction or Palliative Radiation therapy
What are 3 charactertistics of acute toxicity?
1) Occurs during or shortly after therapy
2) Rapidly proliferating tissue
3) Generally “reversible” changes
_____ and _____ is used primarily for local or locoregional disease
External Beam Radiation and Strontium therapy
5 R’s of radiation therapy
1) Repair (the DNA damage)
2) Repopulation
3) Redistribution
4) Reoxygenation (tumor cells can be hypoxic)
5) Radiosensitive
What are 5 characteristics of late toxicity?
1) Occurs more than 3-6 months after radiation therapy
2) Dose limiting
3) Severity very dependent on dose per fraction
4) Secondary to vascular damage, fibrosis and/or loss of parenchymal cells
5) Progressive & irreparable
Type of therapy that is used for:
- benign skin lesions, superficial cancers
- in canine, equine, and bovine
- for superficial lesions only, less than 1-1.5 cm
Cryotherapy
