Automatic selection of lung cancer patients for adaptive radiotherapy using cone-beam CT imaging  Michiel van den Bosch, Michel Öllers, Bart Reymen, Wouter van Elmpt  Physics and Imaging in Radiation Oncology  Volume 1, Pages 21-27 (January 2017) DOI: 10.1016/j.phro.2017.02.005 Copyright © 2017 The Authors Terms and Conditions

Fig. 1 Schematic overview of the first steps of our automatic selection method. The input images are the CT and CBCT scans. The output images contain mass density differences in three different regions of interest (tumour, mediastinum, lungs). Physics and Imaging in Radiation Oncology 2017 1, 21-27DOI: (10.1016/j.phro.2017.02.005) Copyright © 2017 The Authors Terms and Conditions

Fig. 2 (a–c) WEPL-determination in three of the 360 directions starting from an origin that is positioned at the contour center of the mediastinum. Physics and Imaging in Radiation Oncology 2017 1, 21-27DOI: (10.1016/j.phro.2017.02.005) Copyright © 2017 The Authors Terms and Conditions

Fig. 3 (a) 3D scatterplot of non-candidates based on anatomical changes in one region of interest, for example the tumour region. TH1, TH2, TH3 represents the three thresholds that are applied for this region (i.e. 0.5, 1.0 and 1.5cm). ‘Non-typical’ non-candidates (e.g. patients with a breathing artefacts in learning set) are removed, (b) acceptance volume. New patient with a point outside this volume is assigned by the method as candidate for replanning. Physics and Imaging in Radiation Oncology 2017 1, 21-27DOI: (10.1016/j.phro.2017.02.005) Copyright © 2017 The Authors Terms and Conditions

Fig. 4 CT scan, CBCT scan and difference map of the tumour region for (a) non-candidate, (b) candidate. Window/level settings for the CT images and difference maps are equal to the ones shown in Fig. 1. Physics and Imaging in Radiation Oncology 2017 1, 21-27DOI: (10.1016/j.phro.2017.02.005) Copyright © 2017 The Authors Terms and Conditions

Fig. 5 CT scan, CBCT scan and difference map of the tumour region for (a) false negative, (b) false positives due to a change in breathing pattern. Window/level settings for the CT images and difference maps are equal to the ones shown in Fig. 1. Physics and Imaging in Radiation Oncology 2017 1, 21-27DOI: (10.1016/j.phro.2017.02.005) Copyright © 2017 The Authors Terms and Conditions