title: Accuracy and reproducibility of 3D-CT measurements for early response assessment of chemoradiotherapy in patients with oesophageal cancer.
abstract: BACKGROUND
  Chemoradiotherapy is increasingly applied in patients with oesophageal cancer. The aim of the present study was to determine whether 3D-CT volumetry is able to differentiate between responding and non-responding oesophageal tumours early in the course of neoadjuvant chemoradiotherapy.
  
  
  METHODS
  Serial CT before and after two weeks of neoadjuvant chemoradiotherapy was performed in the multimodality treatment arm of a randomised trial including patients with oesophageal carcinoma. CT response was measured with the change in tumour volume between baseline and after 14 days of neoadjuvant therapy. Receiver Operating Characteristic (ROC) analysis was used to evaluate the ability of 3D-CT as an early imaging marker of response.
  
  
  RESULTS
  CT response analysis was performed in 39 patients, of whom 26 patients were histopathological responders. Median tumour volume increased between baseline and after 14 days of chemoradiotherapy in histopathological responders as well as in non-responders, though changes were not statistically significant. The area under the ROC curve was 0.71.
  
  
  CONCLUSIONS
  Tumour volume changes after 14 days of neoadjuvant chemoradiotherapy as measured by 3D-CT were not associated with histopathological tumour response. CT volumetry should not be used for early response assessment in patients with potentially curable oesophageal cancer treated with neoadjuvant chemoradiotherapy.
authors.affiliation: Department of Surgery, Academic Medical Centre, Amsterdam, The Netherlands. m.vanheijl@amc.uva.nl
authors.forename: M
authors.initials: M
authors.lastname: van Heijl
authors.forename: S S K S
authors.initials: SS
authors.lastname: Phoa
authors.forename: M I
authors.initials: MI
authors.lastname: van Berge Henegouwen
authors.forename: J M T
authors.initials: JM
authors.lastname: Omloo
authors.forename: B M
authors.initials: BM
authors.lastname: Mearadji
authors.forename: G W
authors.initials: GW
authors.lastname: Sloof
authors.forename: P M M
authors.initials: PM
authors.lastname: Bossuyt
authors.forename: M C C M
authors.initials: MC
authors.lastname: Hulshof
authors.forename: D J
authors.initials: DJ
authors.lastname: Richel
authors.forename: J J G H M
authors.initials: JJ
authors.lastname: Bergman
authors.forename: F J W
authors.initials: FJ
authors.lastname: Ten Kate
authors.forename: J
authors.initials: J
authors.lastname: Stoker
authors.forename: J J B
authors.initials: JJ
authors.lastname: van Lanschot
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D019540:Area Under Curve; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy; D059186:Chemoradiotherapy, Adjuvant; D003287:Contrast Media; D004938:Esophageal Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D016629:Esophagectomy / Q000379:methods; D004943:Esophagogastric Junction; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D021621:Imaging, Three-Dimensional; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D009367:Neoplasm Staging; D015588:Observer Variation; D049268:Positron-Emission Tomography / Q000379:methods; D011237:Predictive Value of Tests; D012372:ROC Curve; D018401:Sample Size; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D019788:Fluorodeoxyglucose F18