Tumor Dose Specification for External Photon Beams (ICRU Volumes)

GROSS TUMOR VOLUME

is the gross demonstrable extent and location of the tumor.

GROSS TUMOR VOLUME

may consist of primary tumor, metastatic lymphadenopathy, or other metastases

biopsy

GROSS TUMOR VOLUME can be identified through __

CLINICAL TARGET VOLUME

represents the true extent & location of the tumor

CLINICAL TARGET VOLUME

includes GTV plus a margin to account microscopic containing residual disease.

CLINICAL TARGET VOLUME

how to manage: adjuvant - prophylactic treatment; can't be identified thru biopsy

INTERNAL TARGET VOLUME

compensation for internal physiologic movements (breathing, involuntary movements of the muscle, thoracic area movements, etc) and variation in size, shape, and position of the CTV during treatment (voluntary movement, px motion)

PLANNING TARGET VOLUME

The volume that includes CTV with an internal margin (IM) (physiological movements) as well as a setup margin (SM) for patient movement and setup uncertainties (machine itself)

internal margin (IM)

patient movement (physiological movements)

setup margin (SM)

setup uncertainties (machine itself)

TREATED VOLUME

Additional margins provided around the target volume to allow for limitations of the treatment technique (machine and patient)

IRRADIATED VOLUME

The volume of tissue receiving a significant dose

MAXIMUM TARGET DOSE

The highest dose in the target area is called the maximum target dose, provided this dose covers

MINIMUM TARGET DOSE

The minimum target dose is the lowest absorbed dose in the target area.

HOT SPOT

An area outside the target that receives a higher dose than the specified target dose.

2 cm squared

Like the maximum target dose, a hot spot is considered clinically meaningful only if it covers an area of at least __