title: Stereotactic body radiotherapy for centrally located stage I NSCLC: a multicenter analysis.
abstract: OBJECTIVE
  The purpose of this work is to analyze patterns of care and outcome after stereotactic body radiotherapy (SBRT) for centrally located, early-stage, non-small cell lung cancer (NSCLC) and to address the question of potential risk for increased toxicity in this entity.
  
  
  METHODS
  A total of 90 patients with centrally located NSCLC were identified among 613 cases in a database of 13 German and Austrian academic radiotherapy centers. The outcome of centrally located NSCLC was compared to that of cases with peripheral tumor location from the same database.
  
  
  RESULTS
  Patients with central tumors most commonly presented with UICC stage IB (50 %), while the majority of peripheral lesions were stage IA (56 %). Average tumor diameters were 3.3 cm (central) and 2.8 cm (peripheral). Staging PET/CT was available for 73 and 74 % of peripheral and central tumors, respectively. Biopsy was performed in 84 % (peripheral) and 88 % (central) of cases. Doses varied significantly between central and peripheral lesions with a median BED10 of 72 Gy and 84 Gy, respectively (p < 0.001). Fractionation differed as well with medians of 5 (central) and 3 (peripheral) fractions (p < 0.001). In the Kaplan-Meier analysis, 3-year actuarial overall survival was 29 % (central) and 51 % (peripheral; p = 0.004) and freedom from local progression was 52 % (central) and 84 % (peripheral; p < 0.001). Toxicity after treatment of central tumors was low with no grade III/IV and one grade V event. Mortality rates were 0 and 1 % after 30 and 60 days, respectively.
  
  
  CONCLUSIONS
  Local tumor control in patients treated with SBRT for centrally located, early-stage NSCLC was favorable, provided ablative radiation doses were prescribed. This was, however, not the case in the majority of patients, possibly due to concerns about treatment-related toxicity. Reported toxicity was low, but prospective trials are needed to resolve the existing uncertainties and to establish safe high-dose regimens for this cohort of patients.
authors.affiliation: Klinik für Strahlenheilkunde, Universitätsklinik Freiburg, Robert-Koch-Str. 3, 79106, Freiburg, Germany, Daniel.Schanne@uniklinik-freiburg.de.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Schanne
authors.forename: Ursula
authors.initials: U
authors.lastname: Nestle
authors.forename: Michael
authors.initials: M
authors.lastname: Allgäuer
authors.forename: Nicolaus
authors.initials: N
authors.lastname: Andratschke
authors.forename: Steffen
authors.initials: S
authors.lastname: Appold
authors.forename: Ute
authors.initials: U
authors.lastname: Dieckmann
authors.forename: Iris
authors.initials: I
authors.lastname: Ernst
authors.forename: Ute
authors.initials: U
authors.lastname: Ganswindt
authors.forename: Anca L
authors.initials: AL
authors.lastname: Grosu
authors.forename: Richard
authors.initials: R
authors.lastname: Holy
authors.forename: Michael
authors.initials: M
authors.lastname: Molls
authors.forename: Meinhard
authors.initials: M
authors.lastname: Nevinny-Stickel
authors.forename: Sabine
authors.initials: S
authors.lastname: Semrau
authors.forename: Florian
authors.initials: F
authors.lastname: Sterzing
authors.forename: Andrea
authors.initials: A
authors.lastname: Wittig
authors.forename: Matthias
authors.initials: M
authors.lastname: Guckenberger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria; D001706:Biopsy; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D019583:Dose Fractionation, Radiation; D005260:Female; D019788:Fluorodeoxyglucose F18; D005858:Germany; D006801:Humans; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000473:pathology / Q000528:radiation effects; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods*; D011879:Radiotherapy Dosage; D012306:Risk
chemical_list: D019788:Fluorodeoxyglucose F18