title: Predictors and Patterns of Regional Recurrence Following Lung SBRT: A Report From the Elekta Lung Research Group.
abstract: The objective of this study was to determine the predictors and patterns of regional recurrence (RR) following stereotactic body radiotherapy (SBRT) for primary lung cancers.
  
  
  
  Details of patient factors, treatment, and outcome factors were extracted from a multi-institutional (5) database. All events were calculated from the end of radiotherapy. Estimates of local recurrence, RR, and distant metastases (DM) were calculated using the competing risk method. Cause-specific and overall survival were calculated using the Kaplan-Meier method. Details of locations and number of simultaneous RRs were categorized by lymph node anatomic station.
  
  
  
  A total of 734 patients were analyzed. The median follow-up was 3.0 years in surviving patients. Four hundred seventy-six (65%) patients had pathologic proof of disease. There were 64 patients with RR. The 2-year local recurrence, RR, and distant metastases rates were 5.6%, 9.0%, and 14.6% respectively. The 2-year cause-specific and overall survival were 89.9% and 63.7%, respectively. There were 136 simultaneous sites of RR. There were 21 recurrences in stations 4R (15.4%), 9 (6.6%) in 4L, 30 (22%) in 7, 19 (13.9%) in 10R, and 14 (10.3%) in 10L. The most common stations for isolated recurrence (n = 19) were station 7 (n = 5; 26.3%) and station 10R (n = 6; 31.6%). The most common RR levels were stations 4 and 7 for right and left upper lobe, stations 5, 7, and 10 for left lower lobe tumors, and stations 7 and 10 for right lower lobe tumors.
  
  
  
  Stations 4, 7, and 10 were the most common stations for RR. These patterns of recurrence may guide nodal staging procedures prior to SBRT.
authors.affiliation: Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada. Electronic address: meredith.giuliani@rmp.uhn.on.ca.
authors.forename: Meredith E
authors.initials: ME
authors.lastname: Giuliani
authors.affiliation: Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hope
authors.affiliation: Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI.
authors.forename: Victor
authors.initials: V
authors.lastname: Mangona
authors.affiliation: Department of Radiation Oncology, University of Zurich, Zurich, Switzerland; Department of Radiation Oncology, University of Wuerzburg, Wuerzburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Guckenberger
authors.affiliation: Department of Radiation Oncology, University of Wuerzburg, Wuerzburg, Germany.
authors.forename: Frederick
authors.initials: F
authors.lastname: Mantel
authors.affiliation: Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Heike
authors.initials: H
authors.lastname: Peulen
authors.affiliation: Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Jan-Jakob
authors.initials: JJ
authors.lastname: Sonke
authors.affiliation: Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: José
authors.initials: J
authors.lastname: Belderbos
authors.affiliation: Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA.
authors.forename: Maria
authors.initials: M
authors.lastname: Werner-Wasik
authors.affiliation: Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI.
authors.forename: Hong
authors.initials: H
authors.lastname: Ye
authors.affiliation: Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI.
authors.forename: Inga S
authors.initials: IS
authors.lastname: Grills
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000601:surgery*; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007390:International Agencies; D008175:Lung Neoplasms / Q000473:pathology / Q000601:surgery*; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology; D009367:Neoplasm Staging; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D016634:Radiosurgery; D011879:Radiotherapy Dosage; D015996:Survival Rate
keywords: EBUS; Patterns of failure; SABR; Staging; Stereotactic body radiotherapy