Vacuum immobilisation reduces tumour excursion and minimises intrafraction error in a cohort study of stereotactic ablative body radiotherapy for pulmonary metastases

Abstract

Introduction The purpose of this study is to assess the impact of a vacuum immobilisation system on reproducibility of patient set-up, interfraction stability and tumour motion amplitude. Methods From February 2010 to February 2012 as part of a prospective clinical trial 12 patients with solitary pulmonary metastases had consecutive four-dimensional computed tomography (4DCT) scans performed with and without vacuum immobilisation. The displacement of the tumour centroid position was recorded in each of the 10 phases of the 4DCT reconstruction. A further six patients with seven metastases underwent single fraction stereotactic ablative body radiotherapy (SABR) during this period (a total of 1..