title: Electromagnetic navigation bronchoscopy-guided fiducial placement for robotic stereotactic radiosurgery of lung tumors: a feasibility study.
abstract: BACKGROUND
  Stereotactic radiosurgery (Cyberknife; Accuray Incorporated; Sunnyvale, CA) is a treatment option for patients who are medically unfit to undergo lung tumor resection. For precise tumor ablation, the Cyberknife requires fiducial marker placement in or near the target tumor. Fiducial placement under transthoracic CT guidance is associated with a high risk of iatrogenic pneumothorax. Electromagnetic navigation bronchoscopy (ENB) may offer a less morbid alternative to accurately deploy fiducials to bronchoscopically invisible peripheral lung lesions.
  
  
  OBJECTIVE
  Open-label, feasibility study to assess fiducial placement in peripheral lung tumors by ENB.
  
  
  METHODS
  Consecutive patients with peripheral lung tumors and who were evaluated to be nonsurgical candidates underwent fiducial placement under ENB. This procedure was considered successful if fiducials were placed in or near the tumors and remained in place without migration for radiosurgery to proceed. The need for alternative or additional intrathoracic fiducial placement was documented as procedure failure.
  
  
  RESULTS
  A total of 39 fiducials markers were successfully deployed in eight of nine patients (89%). Of these eight successful cases, seven had fiducials placed directly within the tumor (88%). At Cyberknife planning, 7 to 10 days after fiducial placement, 35 of 39 fiducial markers (90%) were still in place and were adequate to allow radiosurgery to proceed. No immediate bronchoscopic complications were observed. One patient had a COPD exacerbation. Another patient returned within 1 day with transient, self-limiting fever.
  
  
  CONCLUSIONS
  ENB can be used to deploy fiducial markers for Cyberknife radiosurgery of lung tumors safely and accurately without the complications associated with transthoracic placement.
authors.affiliation: Interventional Pulmonology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Ave, Boston MA 02215, USA.
authors.forename: Devanand
authors.initials: D
authors.lastname: Anantham
authors.forename: David
authors.initials: D
authors.lastname: Feller-Kopman
authors.forename: Lakshmi N
authors.initials: LN
authors.lastname: Shanmugham
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Berman
authors.forename: Malcolm M
authors.initials: MM
authors.lastname: DeCamp
authors.forename: Sidhu P
authors.initials: SP
authors.lastname: Gangadharan
authors.forename: Ralf
authors.initials: R
authors.lastname: Eberhardt
authors.forename: Felix
authors.initials: F
authors.lastname: Herth
authors.forename: Armin
authors.initials: A
authors.lastname: Ernst
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001999:Bronchoscopy / Q000379:methods*; D002277:Carcinoma / Q000473:pathology / Q000601:surgery*; D055590:Electromagnetic Phenomena; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000295:instrumentation*; D012371:Robotics; D025321:Surgery, Computer-Assisted / Q000379:methods*