Motion mitigation for lung cancer patients treated with active scanning proton therapy.

ABSTRACT:

Purpose

Motion interplay can affect the tumor dose in scanned proton beam therapy. This study assesses the ability of rescanning and gating to mitigate interplay effects during lung treatments.

Methods

The treatments of five lung cancer patients [48 Gy(RBE)/4fx] with varying tumor size (21.1-82.3 cm(3)) and motion amplitude (2.9-30.6 mm) were simulated employing 4D Monte Carlo. The authors investigated two spot sizes (σ ∼ 12 and ∼ 3 mm), three rescanning techniques (layered, volumetric, breath-sampled volumetric) and respiratory gating with a 30% duty cycle.

Results

For 4/5 patients, layered rescanning 6/2 times (for the small/large spot size) maintains equivalent uniform dose within the target >98% for a single fraction. Breath sampling the timing of rescanning is ∼

SUBMITTER: Grassberger C 

PROVIDER: S-EPMC4409624 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature