“…Several approaches have been developed in order to quantify and characterize the geometrical uncertainties produced by organ motion and deformation between fractions, including: serial imaging measurement of the organ during treatment course (Roeske et al, 1995;van Herk et al, 1995;Ten Haken et al, 1991), fiducial markers (Crook et al, 1995;Balter et al, 1995), margins of organs at risk (OAR) (Thor et al, 2010;Mageras et al, 1999;Stroom et al, 1999), rigid-body motion (Thor et al, 2013a;Killoran et al, 1997;Craig et al, 2001), parametrization of the organ structure (Hoogeman et al, 2002;Mageras et al, 1996;Pavel-Mititean et al, 2004), as well as biomechanical (Yan et al, 1999) and statistical models (Fontenla et al, 2001a,b;Söhn et al, 2012;Budiarto et al, 2011;Thörnqvist et al, 2013;Bondar et al, 2014;Rios et al, 2016). Recently, a method based on weighted scenarios of the fundamental directions of the patient's geometric variability was implemented (Söhn et al, 2005;Budiarto et al, 2011).…”