Curative treatment of lung cancer is difficult because of organ motions. A treatment improvement consists in tracking the tumour displacement and deformation during patient breathing in order to optimise the ballistics of the particles. The aim of this work is to simulate the motions and deformations of the lung using personalised parameters for each patient. At LIRIS, we work on tumour deformations simulation based on an inflatable elastic model of object in interaction with its environment (the rib cage). We study the finite-element models or simplified models such as mass-spring type or particle system.