title: Mapping of failures after radiochemotherapy in patients with non-metastatic esophageal cancer: A posteriori analysis of the dose distribution in the sites of loco-regional relapse.
abstract: OBJECTIVE
  We aimed to evaluate the patterns of loco-regional failure (LRF) after exclusive chemoradiotherapy (eCRT) for esophageal cancer with respect to planned dose and/or the incidental (unplanned) dose outside target volumes.
  
  
  METHODS
  Co-image registration of CT or (18)F-FDG PET-CT at the time of failure (tf) and at the time of CRT (t0) was performed in 34 patients with LRF. Dosimetric parameters with regard to local failure (LF), nodal failure (NF) and involved nodal stations (NS) were derived.
  
  
  RESULTS
  Twenty-two patients (64.7%) had LF, the majority of which (95.5%) were located at the epicenter of the GTV of the primary tumor. The mean doses recalculated to the NS at tf were more likely to be lower than the planned dose delivered to the PTV at t0: Dmean=33.9 ± 20.8 Gy vs 52.2 ± 8.5 Gy (p=0.0009), D95%=27.5 ± 21 Gy vs 46.1 ± 4.8 Gy (p=0.004). Among the 12 patients with NF outside the elective nodal irradiation (ENI) volume, Dmean of NS outside the ENI was significantly lower (19.4 ± 21.4 Gy) than the Dmean of NS with failure within the ENI (45.1 ± 6.1 Gy, p=0.01).
  
  
  CONCLUSIONS
  Loco-regional failure after exclusive chemoradiotherapy for esophageal cancer may be due to an inadequately low dose.
authors.affiliation: Medical Imaging Group, Laboratory of Electronics, Computer Science and Imaging, (Le2I), CNRS 6306, University of Burgundy, France; Department of Radiation Oncology, University Hospital of Besançon, France.
authors.forename: Coraline
authors.initials: C
authors.lastname: Bednarek
authors.affiliation: Medical Imaging Group, Laboratory of Electronics, Computer Science and Imaging, (Le2I), CNRS 6306, University of Burgundy, France; Department of Radiation Oncology, Georges François Leclerc Cancer Center, Dijon, France. Electronic address: gcrehange@cgfl.fr.
authors.forename: Gilles
authors.initials: G
authors.lastname: Crehange
authors.affiliation: Medical Imaging Group, Laboratory of Electronics, Computer Science and Imaging, (Le2I), CNRS 6306, University of Burgundy, France; Department of Radiation Oncology, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Magali
authors.initials: M
authors.lastname: Quivrin
authors.affiliation: Department of Statistics, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Adèle
authors.initials: A
authors.lastname: Cueff
authors.affiliation: Department of Radiation Oncology, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Noémie
authors.initials: N
authors.lastname: Vulquin
authors.affiliation: Department of Radiation Oncology, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Cédric
authors.initials: C
authors.lastname: Chevalier
authors.affiliation: Department of Radiation Oncology, University Hospital of Besançon, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Cerda
authors.affiliation: Department of Medical Physics, University Hospital of Besançon, France.
authors.forename: Yolande
authors.initials: Y
authors.lastname: Petegnief
authors.affiliation: Department of Medical Physics, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mazoyer
authors.affiliation: Department of Radiation Oncology, Georges François Leclerc Cancer Center, Dijon, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Maingon
authors.affiliation: Department of Radiation Oncology, University Hospital of Besançon, France.
authors.forename: Jean François
authors.initials: JF
authors.lastname: Bosset
authors.affiliation: Department of Radiation Oncology, University Hospital of Besançon, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Servagi Vernat
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy; D004938:Esophageal Neoplasms / Q000628:therapy*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008198:Lymph Nodes / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed; D017211:Treatment Failure
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Elective nodal irradiation; Esophageal cancer; Exclusive chemoradiotherapy; Patterns of loco-regional failure