title: Intravascular Placement of Metallic Coils as Lung Tumor Markers for CyberKnife Stereotactic Radiation Therapy.
abstract: OBJECTIVE
  To present our experience with placing endovascular coils in pulmonary arteries used as a fiducial marker for CyberKnife therapy and to describe the technical details and complications of the procedure.
  
  
  METHODS
  Between June 2005 and September 2013, 163 patients with primary or secondary lung malignancies, referred for fiducial placement for stereotactic radiosurgery, were retrospectively reviewed. Fourteen patients (9 men, 5 women; mean age, 70 years) with a history of pneumonectomy (n = 3), lobectomy (n = 3) or with severe cardiopulmonary co-morbidity (n = 8) underwent coil (fiducial marker) placement. Pushable or detachable platinum micro coils (n = 49) 2-3 mm in size were inserted through coaxial microcatheters into a small distal pulmonary artery in the vicinity of the tumor under biplane angiography/fluoroscopy guidance.
  
  
  RESULTS
  Forty nine coils with a median number of 3 coils per tumor were placed with a mean tumor-coil distance of 2.7 cm. Forty three (87.7%) of 49 coils were successfully used as fiducial markers. Two coils could not be used due to a larger tumor-coil distance (> 50 mm). Four coils were in an acceptable position but their non-coiling shape precluded tumor tracking for CyberKnife treatment. No major complications needing further medication other than nominal therapy, hospitalization more than one night or permanent adverse sequale were observed.
  
  
  CONCLUSIONS
  Endovascular placement of coil as a fiducial marker is safe and feasible during CyberKnife therapy, and might be an option for the patients in which percutaneous transthoracic fiducial placement might be risky.
authors.affiliation: Department of Radiology, Anadolu Medical Center, Kocaeli 41400, Turkey.
authors.forename: Kutlay
authors.initials: K
authors.lastname: Karaman
authors.affiliation: Department of Radiology, Anadolu Medical Center, Kocaeli 41400, Turkey.
authors.forename: A Murat
authors.initials: AM
authors.lastname: Dokdok
authors.affiliation: Department of Radiology, Anadolu Medical Center, Kocaeli 41400, Turkey.
authors.forename: Oktay
authors.initials: O
authors.lastname: Karadeniz
authors.affiliation: Department of Radiology, Anadolu Medical Center, Kocaeli 41400, Turkey.
authors.forename: Cemile
authors.initials: C
authors.lastname: Ceylan
authors.affiliation: Department of Radiation Oncology, Anadolu Medical Center, Kocaeli 41400, Turkey.
authors.forename: Kayıhan
authors.initials: K
authors.lastname: Engin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D057918:Fiducial Markers; D006801:Humans; D008168:Lung / Q000601:surgery; D008175:Lung Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010984:Platinum; D011013:Pneumonectomy; D011651:Pulmonary Artery; D016634:Radiosurgery / Q000379:methods*; D012189:Retrospective Studies
chemical_list: D010984:Platinum
keywords: CyberKnife; Fiducial marker; Lung neoplasm