title: Influence of Institutional Experience and Technological Advances on Outcome of Stereotactic Body Radiation Therapy for Oligometastatic Lung Disease.
abstract: Many technological and methodical advances have made stereotactic body radiotherapy (SBRT) more accurate and more efficient during the last years. This study aims to investigate whether experience in SBRT and technological innovations also translated into improved local control (LC) and overall survival (OS).
  
  
  
  A database of 700 patients treated with SBRT for lung metastases in 20 German centers between 1997 and 2014 was used for analysis. It was the aim of this study to investigate the impact of fluorodeoxyglucose positron-emission tomography (FDG-PET) staging, biopsy confirmation, image guidance, immobilization, and dose calculation algorithm, as well as the influence of SBRT experience, on LC and OS.
  
  
  
  Median follow-up time was 14.3 months (range, 0-131.9 months), with 2-year LC and OS of 81.2% (95% confidence interval [CI] 75.8%-85.7%) and 54.4% (95% CI 50.2%-59.0%), respectively. In multivariate analysis, all treatment technologies except FDG-PET staging did not significantly influence outcome. Patients who received pre-SBRT FDG-PET staging showed superior 1- and 2-year OS of 82.7% (95% CI 77.4%-88.6%) and 64.8% (95% CI 57.5%-73.3%), compared with patients without FDG-PET staging resulting in 1- and 2-year OS rates of 72.8% (95% CI 67.4%-78.8%) and 52.6% (95% CI 46.0%-60.4%), respectively (P=.012). Experience with SBRT was identified as the main prognostic factor for LC: institutions with higher SBRT experience (patients treated with SBRT within the last 2 years of the inclusion period) showed superior LC compared with less-experienced centers (P≤.001). Experience with SBRT within the last 2 years was independent from known prognostic factors for LC.
  
  
  
  Investigated technological and methodical advancements other than FDG-PET staging before SBRT did not significantly improve outcome in SBRT for pulmonary metastases. In contrast, LC was superior with increasing SBRT experience of the individual center.
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany. Electronic address: juliane.rieber@med.uniheidelberg.de.
authors.forename: Juliane
authors.initials: J
authors.lastname: Rieber
authors.affiliation: Department of Radiation Oncology, University Hospital Jena, Jena, Germany.
authors.forename: Nasrin
authors.initials: N
authors.lastname: Abbassi-Senger
authors.affiliation: Department of Radiation Oncology, University Hospital Freiburg, Freiburg, Germany; German Cancer Consortium, Heidelberg, Partner Site Freiburg, Freiburg, Germany.
authors.forename: Sonja
authors.initials: S
authors.lastname: Adebahr
authors.affiliation: Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Department of Radiation Oncology, University of Rostock, Rostock, Germany.
authors.forename: Nicolaus
authors.initials: N
authors.lastname: Andratschke
authors.affiliation: Department of Radiation Oncology, Universitätsklinikum Schleswig-Holstein, Kiel, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Blanck
authors.affiliation: Department of Radiation Oncology, Technical University Munich, Munich, Germany.
authors.forename: Marciana
authors.initials: M
authors.lastname: Duma
authors.affiliation: Department of Radiation Oncology, University Hospital Aachen, Aachen, Germany.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Eble
authors.affiliation: Department of Radiation Oncology, University Hospital Münster, Münster, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Ernst
authors.affiliation: Department of Radiation Oncology, University Hospital Wuerzburg, Wuerzburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Flentje
authors.affiliation: Department of Radiation Oncology, Ludwig Maximilians University Munich, Munich, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Gerum
authors.affiliation: Department of Radiation Oncology, University Hospital Magdeburg, Magdeburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Hass
authors.affiliation: Department of Radiotherapy and Special Oncology, Medical School Hannover, Hannover, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Henkenberens
authors.affiliation: Department of Radiation Oncology, University of Rostock, Rostock, Germany.
authors.forename: Guido
authors.initials: G
authors.lastname: Hildebrandt
authors.affiliation: Department of Radiation Oncology, University Hospital Frankfurt, Frankfurt, Germany.
authors.forename: Detlef
authors.initials: D
authors.lastname: Imhoff
authors.affiliation: Department of Radiation Oncology, Hospital Augsburg, Augsburg, Germany.
authors.forename: Henning
authors.initials: H
authors.lastname: Kahl
authors.affiliation: Department of Radiation Oncology, Bern University Hospital, Bern, Switzerland.
authors.forename: Nathalie Desirée
authors.initials: ND
authors.lastname: Klass
authors.affiliation: Department of Radiation Oncology, Helios Klinikum Berlin-Buch, Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Krempien
authors.affiliation: Department of Radiation Oncology, Medical Faculty and University Hospital C.G. Carus, Technical University Dresden, Dresden, Germany; German Cancer Research Center, Heidelberg and German Cancer Consortium partner site Dresden, Dresden, Germany; OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Lohaus
authors.affiliation: Department of Radiation Oncology, University Medical Center Mannheim, University of Heidelberg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Lohr
authors.affiliation: Department of Radiation Oncology, University Hospital Hamburg, Hamburg, Germany.
authors.forename: Cordula
authors.initials: C
authors.lastname: Petersen
authors.affiliation: Department of Radiation Oncology, Hospital Heidenheim, Heidenheim, Germany.
authors.forename: Elsge
authors.initials: E
authors.lastname: Schrade
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Streblow
authors.affiliation: Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Uhlmann
authors.affiliation: Department of Radiotherapy and Radiation Oncology, Philipps-University Marburg, University Hospital Giessen and Marburg, Marburg, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Wittig
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany; German Cancer Research Center, Clinical Cooperation Unit Radiation Oncology, Heidelberg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Sterzing
authors.affiliation: Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Department of Radiation Oncology, University Hospital Wuerzburg, Wuerzburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Guckenberger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000704:Analysis of Variance; D002173:Cancer Care Facilities / Q000592:standards*; D002648:Child; D016208:Databases, Factual; D019583:Dose Fractionation, Radiation; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D005858:Germany; D006801:Humans; D007103:Immobilization; D062069:Inventions; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods; D011379:Prognosis; D019275:Radiopharmaceuticals; D016634:Radiosurgery / Q000379:methods*; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18