title: Diffusion-weighted imaging for evaluating lymph node eradication after neoadjuvant chemoradiation therapy in locally advanced rectal cancer.
abstract: BACKGROUND
  As lymph node (LN) eradication is the prerequisite for clinical surveillance or local excision for patients who have achieved a complete response after preoperative chemoradiation therapy (CRT), the radiological evaluation of LN eradication is important.
  
  
  OBJECTIVE
  To evaluate the added value of diffusion-weighted imaging (DWI) in the evaluation of LN eradication after CRT in patients with locally advanced rectal cancer (LARC).
  
  
  METHODS
  Ninety-five consecutive patients (64 men, 31 women; mean age, 59 years; range, 32-82 years) who underwent pre- and post-CRT 1.5-T MRI with DWI (b = 0, 1000 s/mm(2)) were enrolled. To evaluate the added value of DWI in the evaluation of LN eradication after CRT, two radiologists first independently read the pre- and post-CRT T2-weighted (T2W) images and then read the combined T2W imaging set and the pre- and post-CRT DWIs with a 4-week interval. The radiologists recorded their confidence scores for LN eradication using a 5-point scale on a per-patient basis. The diagnostic performances were compared between the two reading sessions for each reader with pair-wise comparisons of receiver-operating characteristic curves. Histopathological reports served as the reference standards for LN eradication.
  
  
  RESULTS
  The study population consisted of an LN-eradicated group (n = 66) and a non-eradicated group (n = 29). The diagnostic performances did not significantly differ between the two reading sessions for the two readers (AUCs for reader 1, 0.770 and 0.774, P = 0.8155; for reader 2, 0.794 and 0.798, P = 0.8588).
  
  
  CONCLUSIONS
  Adding DWI to T2W imaging provided no additional diagnostic benefit for the evaluation of LN eradication following CRT in patients with LARC.
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea.
authors: Kyeong Hwa
authors: KH
authors: Ryu
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea radiresi@gmail.com.
authors: Seung Ho
authors: SH
authors: Kim
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea.
authors: Jung-Hee
authors: JH
authors: Yoon
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea.
authors: Yedaun
authors: Y
authors: Lee
authors: Department of Pathology, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea.
authors: Jin Ho
authors: JH
authors: Paik
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea.
authors: Yun-Jung
authors: YJ
authors: Lim
authors: Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Republic of Korea.
authors: Kwang Hwi
authors: KH
authors: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D059248:Chemoradiotherapy; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D012372:ROC Curve; D012004:Rectal Neoplasms / Q000473:pathology / Q000628:therapy*; D015203:Reproducibility of Results; D016896:Treatment Outcome
keywords: Diffusion-weighted image; lymph node; lymphatic metastasis; neoplasm; rectum