Methods, apparatuses and systems are described for implanting a plurality of fiducial markers into a tissue. Systems include a needle, a stylet sized to slide within a lumen of the needle, and a multi-stop stylet spacer having stopping features configured to engage with the stylet to stop the distal end of the stylet at one or more predetermined distances from the distal end of the needle. Methods for implanting a plurality of fiducial markers into a tissue are described and include inserting a needle preloaded with fiducial markers into a tissue, adjusting a multi-stop stylet spacer from a safety position to a first deployment position, deploying a first fiducial marker into the tissue, adjusting the stylet spacer from the first deployment position to a second deployment position, and deploying a second fiducial marker into the tissue.
