29 - 200 - RADIOTHERAPY Flashcards
Radiation-induced malignancy is a rare but serious side effect, which presents at a median of how many years after treatment?
10 years
refers to the delivery of specified radiation dose in temporally separate treatments, and is recommended to both increase the efficacy of effects on target tissue and to allow normal irradiated tissue to repair radiation damage
Fractionation
unit of radiation dose
gray (Gy)
*defined as 1 joule (J) of energy absorbed per kilogram of tissue
An alternate unit of absorbed dose, largely replaced by the gray
rad (an acronym for radiation absorbed dose)
*1 Gy is equal to 100 rads
Commonly used dose-fractionation schedules for cutaneous malignancies
60 Gy in 30 fractions, and 48 Gy in 12 fractions
The earliest reaction of radiation dermatitis
erythema
*may occur and resolve within hours, and is normally only evident after relatively high-dose exposure.
threshold dose for erythema in radiation dermatitis
2 Gy or greater skin dose
Classify the grade of radiation Dermatitis
Faint erythema
Grade 1
Classify the grade of radiation Dermatitis:
Patchy moist desquamation (mostly confined to skin folds and creases)
Grade 2
Classify the grade of radiation Dermatitis:
Dry Desquamation
Grade 1
Classify the grade of radiation Dermatitis:
Alopecia visible on close inspection
Grade 1
Classify the grade of radiation Dermatitis:
**Atrophy associated with telangiectasia or pigmentation changes **
Grade 1
Classify the grade of radiation Dermatitis:
Mild induration or fibrosisl able to pinch skin
Grade 1
Classify the grade of radiation Dermatitis:
Moderate-to-brisk erythema
Grade 2
Classify the grade of radiation dermatitis:
Moderate edema
Grade 2
Classify the grade of radiation dermatitis:
Hair loss ≥50% of normal
Grade 2
Classify the grade of radiation Dermatitis:
Striae or adnexal structure loss
Grade 2
Classify the grade of radiation dermatitis:
Moderate induration or fibrosis; able to SLIDE skin but unable to pinch
Grade 2
Classify the grade of radiation dermatitis:
**Bleeding induced by minor trauma or abrasion **
Grade 3
Classify the grade of radiation dermatitis:
**Moist desquamation (other than skin folds and creases) **
Grade 3
Classify the grade of radiation dermatitis:
Atrophy = Ulceration
Grade 3
Classify the grade of radiation dermatitis:
**Severe induration or fibrosis; ** unable to slide or pinch, limiting self care
Grade 3
Classify the grade of radiation dermatitis:
**Skin Necrosis **
Grade 4
Classify the grade of radiation dermatitis:
Ulceration of full thickness of dermis
Grade 4
Classify the grade of radiation dermatitis:
**Spontaneous bleeding **
Grade 4
Classify the grade of radiation dermatitis:
Generalized induration or fibrosis; impaired breathing or feeding
Grade 4
Classify the grade of radiation dermatitis:
Death
Grade 5
cutaneous reaction, in response to specific systemic agents, in the area of previous radiation exposure.
Radiation recall
The most commonly cited chemotherapeutic agents in radiation racall are?
anthracyclines, taxanes, and gemcitabine
Cutaneous Indications for Primary or Adjuvant Radiotherapy
The clearest indication for adjuvant radiotherapy treatment
positive surgical margin
other considerations include tumor depth greater than 4 mm in the case of squamous cell cancer or tumor size greater than 2 cm
Commonly-Observed Adverse Events Attributable to Radiation
