title: Dynamic contrast-enhanced MRI: Use in predicting pathological complete response to neoadjuvant chemoradiation in locally advanced rectal cancer.
abstract: OBJECTIVE
  To determine the ability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict pathological complete response (pCR) before preoperative chemoradiotherapy (CRT) in locally advanced rectal cancer.
  
  
  METHODS
  In a prospective clinical trial, 38 enrolled patients underwent pre- and post-CRT DCE-MRI at 3.0T. The tumor length and the following perfusion parameters (K(trans) , kep , ve ) were measured for the tumor and compared between the pCR group and the non-pCR group, as well as before and after CRT. For categorical variable comparison, the Kruskal-Wallis test was used. P < 0.05 was considered significant.
  
  
  RESULTS
  No difference in tumor length was found between the pCR and non-pCR group pre- and post-CRT (P = 0.26 (0.15,0.45), 0.35 (0.21,0.52), respectively). Before CRT, the mean tumor K(trans) in the pCR group was significantly higher than in the non-pCR group (P = 0.01). A K(trans) of 0.66 emerged as the best cutoff for distinguishing pCR from non-pCR. Regarding kep and ve , significant differences were also observed between the pCR and non-pCR groups (P = 0.02, 0.01, respectively). The mean K(trans) , kep , and ve values post-CRT were lower in the pCR group than in the non-pCR group, although there was no significant difference (P = 0.10 (0.04,0.16), 0.11 (0.07,0.26), 0.10 (0.06,0.23), respectively).
  
  
  CONCLUSIONS
  Before neoadjuvant chemoradiotherapy in rectal cancer, DCE-MRI can distinguish between complete and incomplete response using a K(trans) threshold of 0.66 with a sensitivity of 100%.
authors: Department of Radiology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Tong
authors: T
authors: Tong
authors: Department of Radiology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Yiqun
authors: Y
authors: Sun
authors: Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
authors: Marc J
authors: MJ
authors: Gollub
authors: Department of Radiology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Weijun
authors: W
authors: Peng
authors: Department of Colorectal Surgery, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Sanjun
authors: S
authors: Cai
authors: Department of Radiotherapy, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Zhen
authors: Z
authors: Zhang
authors: Department of Radiology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
authors: Yajia
authors: Y
authors: Gu
mesh_terms: D000328:Adult; D000368:Aged; D059248:Chemoradiotherapy; D003131:Combined Modality Therapy; D003287:Contrast Media / Q000737:chemistry*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D010865:Pilot Projects; D057234:Preoperative Period; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy* / Q000601:surgery; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: DCE-MRI; chemoradiotherapy; complete pathological response; rectal cancer