title: [Comparative study of endorectal ultrasonography and magnetic resonance imaging in preoperative staging of rectal cancer].
abstract: OBJECTIVE
  To evaluate the diagnostic value of endorectal ultrasonography (ERUS) and magnetic resonance imaging (MRI) in preoperative staging of rectal carcinoma.
  
  
  METHODS
  A total of 44 patients with biopsy proven rectal tumor underwent preoperative ERUS and MRI examinations. All patients were evaluated to determine the diagnostic accuracy of depth of transmural tumor invasion and lymph node metastases.Imaging results were compared with histopathological findings.
  
  
  RESULTS
  The accuracy of T staging (uT1, uT2, uT3, uT4) for ERUS was 95.5%, 90.9%, 93.2% and 97.7% and the overall accuracy 88.6% (39/44) . The sensitivity was 83.3%, 72.7%, 72.2%, 77.8% and the specificity 97.3%, 92.9%, 96.2% and 97.6%. The accuracy of T staging (T1, T2, T3, T4) for MRI was 93.2%, 90.9%, 93.2%, 100.0% and the overall accuracy 86.4% (38/44) . The sensitivity was 71.4%, 93.8%, 94.4% and 100.0% and the specificity 97.3%, 89.3%, 92.3% and 100.0%. Detection of lymph node metastases:the accuracy of ERUS was 75.0% (33/44), MRI 93.2% (41/44). The sensitivity and specificity was found to be 68.4% (13/19) and 80.0% (20/25) on ERUS, 94.7% (18/19) and 92.0% (23/25) on MRI respectively.
  
  
  CONCLUSIONS
  ERUS and MRI may be used for accurate preoperative staging of rectal cancer.ERUS has higher accuracy and sensitivity for T1 stage while MRI is preferred for lymph node metastasis.
authors.affiliation: Department of Ultrasonography, Beijing Hospital, Ministry of Health, Beijing 100730, China. Email: guofajinbh@163.com.
authors.forename: Fajin
authors.initials: F
authors.lastname: Guo
authors.affiliation: Department of Ultrasonography, Beijing Hospital, Ministry of Health, Beijing 100730, China.
authors.forename: Junhong
authors.initials: J
authors.lastname: Ren
authors.affiliation: Department of Ultrasonography, Beijing Hospital, Ministry of Health, Beijing 100730, China.
authors.forename: Siyu
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Ultrasonography, Beijing Hospital, Ministry of Health, Beijing 100730, China.
authors.forename: Weide
authors.initials: W
authors.lastname: Dai
authors.affiliation: Department of Ultrasonography, Beijing Hospital, Ministry of Health, Beijing 100730, China.
authors.forename: Na
authors.initials: N
authors.lastname: Ma
mesh_terms: D000328:Adult; D000368:Aged; D019160:Endosonography; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000473:pathology