title: [18F]-Fluorodeoxyglucose-positron emission tomography for the assessment of histopathologic response and prognosis after completion of neoadjuvant chemoradiation in esophageal cancer.
abstract: OBJECTIVE
  To evaluate the potential of [(18)F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) after the completion of neoadjuvant chemoradiation for the assessment of histopathologic response and prognosis in the multimodality treatment of patients with esophageal cancer.
  
  
  BACKGROUND
  Combined chemoradiation with and without surgery are widely accepted treatment options for patients with locally advanced esophageal cancer. Evidence suggests that patients with response to chemoradiation have no additional benefit from surgery compared with definitive chemoradiation. However, there is still a great lack in noninvasive markers for response assessment in patients with esophageal cancer undergoing multimodality treatment. Interestingly, recent studies imply that FDG-PET significantly correlates with histopathologic response and survival in patients with esophageal cancer undergoing neoadjuvant chemotherapy followed by surgical resection.
  
  
  METHODS
  Study patients were recruited from a prospective clinical observation trial on neoadjuvant chemoradiation for esophageal cancer between 1997 and 2006. The study included 119 (98 men, 21 women; median age, 59.4 years; squamous cell cancer: 66; adenocarcinoma: 53) patients with locally advanced esophageal cancer (cT2- 4, N(x), M(0)). All patients received neoadjuvant chemoradiation (cisplatin, 5-FU, 36 Gy) and subsequently underwent transthoracic en bloc esophagectomy. Histomorphologic regression was defined as major histopathologic response when resected specimens contained less than 10% vital residual tumor cells (major response: 47 patients [39.5%]; minor response: 72 patients [60.5%]). FDG-PET was performed before and 2 to 3 weeks after the end of chemoradiation with assessment of the intratumoral FDG-uptake (pretreatment standardized uptake value; post-treatment standardized uptake value; percentage change). These variables were correlated with histopathologic response and survival.
  
  
  RESULTS
  Major histomorphologic response was confirmed as an important prognostic factor (P = 0.005; log-rank test). Neoadjuvant chemoradiation led to a significant reduction of intratumoral FDG-uptake (P = 0.0001). A nonsignificant association was seen between major responders and FDG-PET results (P = 0.056). However, the receiver operating characteristic analysis could not identify a standardized uptake value threshold with a relevant predictive value for histomorphologic response. No significant association between metabolic imaging and prognosis was found.
  
  
  CONCLUSIONS
  FDG-PET seems not to be an imaging system that effectively characterizes the groups of major and minor response as well as survival in patients with esophageal cancer after multimodality treatment.
authors: General, Visceral, and Cancer Surgery, University of Cologne, Germany.
authors: Daniel
authors: D
authors: Vallböhmer
authors: Arnulf H
authors: AH
authors: Hölscher
authors: Markus
authors: M
authors: Dietlein
authors: Elfriede
authors: E
authors: Bollschweiler
authors: Stephan E
authors: SE
authors: Baldus
authors: Stefan P
authors: SP
authors: Mönig
authors: Ralf
authors: R
authors: Metzger
authors: Harald
authors: H
authors: Schicha
authors: Matthias
authors: M
authors: Schmidt
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000532:radiotherapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D011446:Prospective Studies; D019275:Radiopharmaceuticals
chemical_list: D000970:Antineoplastic Agents; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18