The success of medical procedures using needles is correlated to the accuracy of the needle insertion in the tissue. The study presented in this paper aims at comparing the results of different prostate brachytherapy protocols concerning needle insertion order and its influence on tissue deformations.Prostate brachytherapy consists in the insertion of radioactive seeds inside the prostate tissue using needles under visual guidance with trans-rectal ultrasound. Depending on the country, hospital and physician, different protocols are used to insert the needles into the prostate. The main difference is related to the order of insertion of the needles. Some protocols perform the insertion of the needles and seeds one by one, checking the position of the seeds with real-time X-ray fluoroscopy at each iteration. Other protocols give priority to the insertion of all needles in a given order and then all the seeds.As prostate and surrounding organs are soft tissues, deformations occur when needles are inserted into the tissues. Independently of factors such as the procedure duration and physician skills, the study of the order of insertion of the needles relatively to the presence and/or location of other needles may give quantitative information about the different deformations undergone by the tissue depending on the protocol. Our comparison study is conducted thanks to a discrete soft tissue model allowing the accurate modelling of needle insertion into soft tissues.Results show that prostatic tissue deformations depend on the protocol used. The ability of soft-tissue modelling methods to compare the consequences of different medical gestures independently of other parameters was also demonstrated through the different simulations.