title: Clinical outcome of image-guided adaptive radiotherapy in the treatment of lung cancer patients.
abstract: BACKGROUND
  Adaptive strategy with daily online tumour match is a treatment option when treating locally advanced lung cancer patients with curative intended radiotherapy (RT).
  
  
  METHODS
  Fifty-two consecutive lung cancer patients treated with soft tissue match, adaptive RT and small planning target volumes (PTV) margins were analysed. A control group of 52 consecutive patients treated with bone match, no adaptive strategy and larger margins was included. Patients were followed with computed tomography (CT) scans every third month. CT-images showing loco-regional recurrences were identified. The recurrence gross tumour volume was delineated and registered with the original radiation treatment plan to identify site of failure. All patients were toxicity-scored using CTCAE 4.03 grading scale. Data were analysed using the Kaplan-Meier analysis.
  
  
  RESULTS
  The median follow-up time was 16 months (3-35). Within a year, 35% of the patients in the adaptive group (ART-group) and 53% in the control group (No-ART-group) experienced loco-regional failure, showing improved loco-regional control in the ART group (p = 0.05). One patient in the ART-group and four patients in the No-ART-group showed marginal failure. Median overall progression-free survival time for the ART-group was 10 months (95% CI 8-12), and 8 months (95% CI 6-9) for the No-ART-group. Severe pneumonitis (grade 3-5) decreased from 22% in the No-ART-group to 18% in the ART-group (non-significant, p = 0.6). No significant difference in severe dysphagia was found between the two groups.
  
  
  CONCLUSIONS
  In the first small cohort of patients investigated, implementation of soft-tissue tumour match and adaptive strategies for locally advanced lung cancer patients increased the loco-regional control rate without increasing treatment-related toxicity.
authors.affiliation: a Department of Oncology , Aarhus University Hospital , Aarhus , Denmark.
authors.forename: Marie
authors.initials: M
authors.lastname: Tvilum
authors.affiliation: a Department of Oncology , Aarhus University Hospital , Aarhus , Denmark.
authors.forename: Azza A
authors.initials: AA
authors.lastname: Khalil
authors.affiliation: b Department of Medical Physics , Aarhus University Hospital , Aarhus , Denmark.
authors.forename: Ditte S
authors.initials: DS
authors.lastname: Møller
authors.affiliation: b Department of Medical Physics , Aarhus University Hospital , Aarhus , Denmark.
authors.forename: Lone
authors.initials: L
authors.lastname: Hoffmann
authors.affiliation: a Department of Oncology , Aarhus University Hospital , Aarhus , Denmark.
authors.forename: Marianne M
authors.initials: MM
authors.lastname: Knap
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D016022:Case-Control Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D017564:Radiation Pneumonitis / Q000453:epidemiology; D061089:Radiotherapy, Image-Guided; D050397:Radiotherapy, Intensity-Modulated