title: The diffusion-weighted magnetic resonance imaging (DWI) predicts the early response of esophageal squamous cell carcinoma to concurrent chemoradiotherapy.
abstract: To investigate the predictive value of serial diffusion-weighted MRI (DWI) on tumor response of the concurrent chemoradiotherapy (CCRT) for esophageal squamous cell carcinoma (ESCC) and to determine the optimal time point of DWI measurements.
  
  
  
  From June 2010 to October 2011, 38 ESCC patients were consecutively enrolled into this prospective cohort study. During their treatment, the longitudinal DWIs were acquired at beginning and every week during the course of CCRT. ADC maps were generated from there DWIs. The tumor responses were evaluated according to the RECIST.
  
  
  
  (1) At completion of CCRT, 20 (52.6%) and 18 (47.4%) patients were evaluated as CR and PR, respectively. Over the time points of measures, the series of ADC values (10-3mm2/s) in whole GTV were consistently characterized with higher (all p<0.05) for these CR patients as their means (std) were 2.24 (0.49), 2.23 (0.51), 2.44 (0.57), 2.54 (0.52), 2.70 (0.46), 2.80 (0.55), 2.92 (0.62), compared with these PR patients as 1.83 (0.31), 1.79 (0.21), 1.87 (0.30), 1.97 (0.37), 2.15 (0.44), 2.26 (0.46), 2.32 (0.51), respectively. However, the ADC change rates (ΔADC) of two groups were found to be similar. These results were also supported by the multivariate ANOVA analyses. The same analysis results of DWI based GTV volumes were also found. (2) The comparisons of logistic regression analysis indicated that only the ADC values at Week 3 (15 fractions) were an independent prognostic factor of tumor response (OR=0.303, p=0.003). ROC curve analysis showed that Area Under Curve for ADC values of the end of 2nd and 3rd weeks were biggest (0.822) and the prediction efficacy was comparatively optimized. The corresponding cut-off values were 2.11 and 2.14 (10-3mm2/s), respectively. (3) Additional analyses on those eight patients with tumor local recurrence within 1year demonstrated the level-off after the continuously increased ADC values till Week 4.
  
  
  
  DWI can be used as a biomarker to predict TE of esophageal cancers in early time during CCRT. The treatment-induced change in ADC of whole GTV during the first 2-3weeks can be highly predictive to TE. The unchanged ADC value in late period may indicate the high tendency of tumor recurrence after 1year.
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China. Electronic address: wlan2006@sina.com.
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Lihong
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China. Electronic address: hanchun2006@126.com.
authors.forename: Chun
authors.initials: C
authors.lastname: Han
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Shutang
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Tian
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Zhensheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Ren
authors.affiliation: Department of Radiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Gaofeng
authors.initials: G
authors.lastname: Shi
authors.affiliation: Department of Radiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Radiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Guangda
authors.initials: G
authors.lastname: Wang
mesh_terms: D000368:Aged; D019540:Area Under Curve; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D000077277:Esophageal Squamous Cell Carcinoma; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D016896:Treatment Outcome
keywords: Apparent diffusion coefficient; Diffusion-weighted magnetic resonance imaging; Esophageal neoplasms; Radiotherapy; Therapeutic effect