Physics Bucharest 2017

Homogeneity

Clinically relevant?

Conformality

Steep dose gradient

Applications

Examples

prostate (rectum), head neck (spinal cord), pelvis

I. Coverage of concave PTV with better sparing of OAR

nasopharyngeal, prostate, head-neck cancer,…

II. Better coverage of tumors near critical structures (also convex) III. Intentionally inhomogeneous dose distributions

SIB, multiple GTV/CTVs...

spine, head-neck,…

IV. Re-irradiation of locally recurrent tumors

brachytherapy

V. Compensation of plans

Potential of IMRT

→ delivery of conventional doses with ↓ toxicity → delivery of higher doses without ↑ toxicity

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