title: Stereotactic body radiotherapy (SBRT) for high-risk central pulmonary metastases.
abstract: OBJECTIVE
  Radiotherapy of central lung tumors carries a higher risk of treatment-related toxicity and local failure. In the era of aggressive oligometastic management the exploration of the proper dose-fractionation for metastatic central lung tumors is essential.
  
  
  METHODS
  Patients diagnosed with high-risk metastatic lesions of the central pulmonary tree comprised this single-institutional retrospective analysis. "High-risk" central pulmonary lesions were defined as those with abutment and/or invasion of the mainstem bronchus. All patients were treated using the CyberKnife SBRT system in 5 fractions to a total dose of 35 or 40 Gy.
  
  
  RESULTS
  Twenty patients were treated from 2008 to 2011 at Georgetown University Hospital. At a median follow up of 19 months, 1-year Kaplan-Meier local control and overall survival was 70 and 75 %, respectively. Late grade 2 or higher atelectasis was the most common treatment-related toxicity and was significantly associated with maximum dose to the mainstem bronchus. Gross endobronchial involvement was associated with significantly lower overall survival.
  
  
  CONCLUSIONS
  Five-fraction SBRT to a total dose of 35 or 40 Gy appears to be a safe and effective management strategy for high-risk central pulmonary metastatic lesions, though care should be taken to limit the maximum point dose to the mainstem bronchus.
authors.affiliation: Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. jonathan.lischalk@gunet.georgetown.edu.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Lischalk
authors.affiliation: Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. ryan.malik@woodhullhc.nychhc.org.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Malik
authors.affiliation: Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. SPC9@gunet.georgetown.edu.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Collins
authors.affiliation: Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. COLLINSB@gunet.georgetown.edu.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Collins
authors.affiliation: Division of Pulmonary, Critical Care, and Sleep Medicine, Pasquerilla Healthcare Center, Georgetown University Hospital, 5th floor, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. ismael.a.matus@gunet.georgetown.edu.
authors.forename: Ismael A
authors.initials: IA
authors.lastname: Matus
authors.affiliation: Division of Pulmonary, Critical Care, and Sleep Medicine, Pasquerilla Healthcare Center, Georgetown University Hospital, 5th floor, 3800 Reservoir Road, NW, Washington, DC, 20007, USA. andersoe@gunet.georgetown.edu.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Anderson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001980:Bronchi / Q000528:radiation effects; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000532:radiotherapy* / Q000556:secondary* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D011379:Prognosis; D011874:Radiometry; D016634:Radiosurgery; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies; D012306:Risk