title: [Clinical value of MR diffusion weighted imaging in prediction of pathological complete response of rectal cancer after neoadjuvant therapy].
abstract: OBJECTIVE
  To evaluate the application value of magnetic resonance diffusion-weighted imaging (DWI) combined with routine T2WI sequence in the determination of pathological complete response (pCR) after neoadjuvant therapy for rectal cancer.
  
  
  METHODS
  Clinical data of 51 cases with locally advanced mid-low rectal cancer undergoing neoadjuvant therapy plus radical resection in the Rectal Cancer Center at The Sixth Affiliated Hospital of Sun Yat-sen University from June 2012 to April 2013 were analyzed retrospectively. Magnetic resonance DWI and T2WI sequences scanning were performed within 1 week before neoadjuvant therapy and within 1 week before operation. Routine single T2WI sequence and DWI combined with T2WI sequence were used separately to predict the residual tumor and to compare with postoperative pathological examination. The prediction values of two methods were compared.
  
  
  RESULTS
  Of 51 patients, 12 cases had pathological complete response (pCR). Prediction of DWI combined T2WI sequence was correct in 8 cases of pCR, whose sensitivity and specificity were higher than those of routine single T2WI sequence (66.7%, 94.9% vs. 33.3%, 84.6%). Prediction value of DWI combined T2WI sequence for pCR was significantly higher as compared to routine single T2WI sequence (AUC, 0.808 vs. 0.590, P=0.001).
  
  
  CONCLUSIONS
  Compared with the routine single T2WI sequence, DWI combined with T2WI sequence can improve the prediction accuracy of pathological complete response.
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou 510655, China. zhouzyang@hotmail.com.
authors.forename: Wu-teng
authors.initials: WT
authors.lastname: Cao
authors.forename: Zhi-yang
authors.initials: ZY
authors.lastname: Zhou
authors.forename: Yan-hong
authors.initials: YH
authors.lastname: Deng
authors.forename: Liang
authors.initials: L
authors.lastname: Kang
authors.forename: Yan-bang
authors.initials: YB
authors.lastname: Lian
authors.forename: Jian-ping
authors.initials: JP
authors.lastname: Qiu
authors.forename: Jia-ying
authors.initials: JY
authors.lastname: Gong
authors.forename: Fei
authors.initials: F
authors.lastname: Xiong
authors.forename: Wen-ru
authors.initials: WR
authors.lastname: Li
authors.forename: Pan
authors.initials: P
authors.lastname: Zhu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D011237:Predictive Value of Tests; D012004:Rectal Neoplasms / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D012680:Sensitivity and Specificity