title: Outcome and prognostic factors of postoperative radiation therapy (PORT) after incomplete resection of non-small cell lung cancer (NSCLC).
abstract: OBJECTIVE
  Current guidelines recommend postoperative radiation therapy (PORT) for incompletely resected non-small cell lung cancer (NSCLC). However, there is still a paucity of evidence for this approach. Hence, we analyzed survival in 78 patients following radiotherapy for incompletely resected NSCLC (R1) and investigated prognostic factors.
  
  
  METHODS
  All 78 patients with incompletely resected NSCLC (R1) received PORT between December 2001 and September 2014. The median total dose for PORT was 60 Gy (range 44-68 Gy). The majority of patients had locally advanced tumor stages (stage IIA (2.6%), stage IIB (19.2%), stage IIIA (57.7%) and stage IIIB (20.5%)). 21 patients (25%) received postoperative chemotherapy.
  
  
  RESULTS
  Median follow-up after radiotherapy was 17.7 months. Three-year overall (OS), progression-free (PFS), local (LPFS) and distant progression-free survival (DPFS) rates were 34.1, 29.1, 44.9 and 51.9%, respectively. OS was significantly prolonged at lower nodal status (pN0/1) and following dose-escalated PORT with total radiation doses >54 Gy (p=0.012, p=0.013). Furthermore, radiation doses >54 Gy significantly improved PFS, LPFS and DPFS (p=0.005; p=0.050, p=0.022). Interestingly, survival was neither significantly influenced by R1 localization nor by extent (localized vs. diffuse). Multivariate analyses revealed lower nodal status and radiation doses >54.0 Gy as the only independent prognostic factors for OS (p=0.021, p=0.036).
  
  
  CONCLUSIONS
  For incompletely resected NSCLC, PORT is used for improving local tumor control. Local progression is still the major pattern of failure. Radiation doses >54 Gy seem to support improved local control and were associated with better OS in this retrospective study.
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Rieber
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Deeg
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg, Germany.
authors.forename: Elena
authors.initials: E
authors.lastname: Ullrich
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Foerster
authors.affiliation: Department of Radiation Oncology, Klinikum am Gesundbrunnen, SLK-Kliniken Heilbronn GmbH, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Bischof
authors.affiliation: Department of Pathology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Warth
authors.affiliation: Department of Pathology, University Hospital Saarland, Homburg, Germany.
authors.forename: Philipp A
authors.initials: PA
authors.lastname: Schnabel
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Muley
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany.
authors.forename: Jutta
authors.initials: J
authors.lastname: Kappes
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik gGmbH, University Hospital Heidelberg, Heidelberg, Germany; Department of Diagnostic and Interventional Radiology, University-HospitalHeidelberg, Heidelberg, Germany.
authors.forename: Claus Peter
authors.initials: CP
authors.lastname: Heussel
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Welzel
authors.affiliation: Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Thomas
authors.affiliation: Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Steins
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg, Germany.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Dienemann
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Debus
authors.affiliation: Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany; Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Hoffmann
authors.affiliation: Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Germany. Electronic address: stefan.rieken@med.uni-heidelberg.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rieken
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000473:pathology / Q000532:radiotherapy; D011184:Postoperative Period; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Incompletely resected NSCLC; Lung cancer; Microscopic residual disease; Non-small cell lung cancer (NSCLC); Postoperative radiation therapy (PORT)