Linear-Endobronchial Ultrasound-Guided Insertion of a Fiducial Marker: A New Tool for Tracking Central Lesions.

Stereotactic body radiotherapy (SBRT) is an effective method for the treatment of localized primary lung tumors. Cyberknife, a highly accurate SBRT technique, follows the target during respiratory cycles using a metallic fiducial marker (FM) previously inserted into the lesion. Various methods have been described for the placement of an FM in peripheral pulmonary lesions; however, none of these is appropriate for mediastinal or hilar tumors. The placement of FMs in central lesions to achieve accurate SBRT is particularly relevant due to their higher mobility during respiratory and cardiac cycles. Here, we describe the use of linear-endobronchial ultrasound for the insertion of an FM marker in a centrally located metastatic melanoma, thereby allowing subsequent treatment with Cyberknife.