title: Accuracy of endorectal ultrasonography in staging locally advanced rectal cancer after preoperative chemoradiation.
abstract: OBJECTIVE
  The aim of our study was to determine the accuracy of endorectal ultrasonography (ERUS) in staging locally advanced rectal cancer after preoperative neoadjuvant chemoradiation and to point out the most common reasons for false interpretation.
  
  
  METHODS
  Forty-four patients with locally advanced rectal cancer received neoadjuvant chemoradiation followed by radical surgery. Restaging was done 1-2 weeks before surgery and the results of ERUS staging were compared with histopathology findings of the resected specimen.
  
  
  RESULTS
  The accuracy of ERUS for T stage after chemoradiation was 75% (33/44). Overstaging occurred in 18% (8/44) of patients, and 7% (3/44) were understaged. The majority of overstaging occurred in patients with ERUS T3 tumors, eventually found to have pathological pT0-pT2 staging. Five patients (11.4%) had complete histology regression and only one of these patients was staged correctly while others were overstaged. In the detection of perirectal lymph node metastases, ERUS was accurate in 68% of patients (30/44). Twenty percent (9/44) of patients were overstaged and 11% were (5/44) understaged.
  
  
  CONCLUSIONS
  ERUS provides a good accuracy rate for staging rectal cancer after neoadjuvant chemoradiation. However, it is insufficient in detection of complete pathological response.
authors.affiliation: Department of Surgical Oncology, Oncology Institute of Vojvodina, Institutski put 4, 21204, Sremska Kamenica-Novi Sad, Serbia. zoran.r@eunet.yu
authors.forename: Zoran
authors.initials: Z
authors.lastname: Radovanovic
authors.forename: M
authors.initials: M
authors.lastname: Breberina
authors.forename: T
authors.initials: T
authors.lastname: Petrovic
authors.forename: A
authors.initials: A
authors.lastname: Golubovic
authors.forename: D
authors.initials: D
authors.lastname: Radovanovic
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D003131:Combined Modality Therapy; D019160:Endosonography / Q000379:methods*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging / Q000379:methods*; D011300:Preoperative Care; D011879:Radiotherapy Dosage; D012004:Rectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy
chemical_list: D002955:Leucovorin; D005472:Fluorouracil