title: cT3N0 rectal cancer: potential overtreatment with preoperative chemoradiotherapy is warranted.
abstract: OBJECTIVE
  Although combined-modality therapy (CMT) is the preferred treatment for T3 and/or lymph node (LN)-positive rectal cancer, the German rectal cancer study published in 2004 demonstrated that 18% of patients deemed suitable for preoperative CMT by endorectal ultrasound (ERUS) may be overstaged. Because data also suggest that LN-negative rectal cancer after total mesorectal excision may not require radiotherapy, it is reasonable to consider omitting radiotherapy for the cT3N0 subset. We therefore determined the accuracy of pre-CMT ERUS or magnetic resonance imaging (MRI) staging, to explore the validity of a nonpreoperative CMT approach for cT3N0 disease.
  
  
  METHODS
  One hundred eighty-eight ERUS-/MRI-staged T3N0 rectal cancer patients received preoperative CMT (fluorouracil based and 45-50.4 Gy) followed by radical resection. Rates of pathologic complete response (pCR) and mesorectal LN involvement were determined.
  
  
  RESULTS
  Tumors were located a median of 5 cm from the anal verge. Sphincter-preserving surgery was performed in 143 patients (76%). Overall pCR was 20%, and 41 patients (22%) had pathologically positive mesorectal LNs. The incidence of positive LNs significantly increased with T stage: ypT0, 3%; ypT1, 7%; ypT2, 20%; ypT3-4, 36% (P = .001).
  
  
  CONCLUSIONS
  The accuracy of preoperative ERUS/MRI for staging mid to distal cT3N0 rectal cancer is limited because 22% of patients have undetected mesorectal LN involvement despite CMT. Therefore, ERUS-/MRI-staged T3N0 rectal cancer patients should continue to receive preoperative CMT. Although 18% may be overstaged and therefore overtreated, our data suggest that an even larger number would be understaged and require postoperative CMT, which is associated with significantly inferior local control, higher toxicity, and worse functional outcome.
authors.affiliation: Department of Surgery, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA. guillemj@mskcc.org
authors.forename: José G
authors.initials: JG
authors.lastname: Guillem
authors.forename: Juan A
authors.initials: JA
authors.lastname: Díaz-González
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Minsky
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Valentini
authors.forename: Seung-Yong
authors.initials: SY
authors.lastname: Jeong
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Rodriguez-Bigas
authors.forename: Claudio
authors.initials: C
authors.lastname: Coco
authors.forename: Rebecca
authors.initials: R
authors.lastname: Leon
authors.forename: José L
authors.initials: JL
authors.lastname: Hernandez-Lizoain
authors.forename: José J
authors.initials: JJ
authors.lastname: Aristu
authors.forename: Elyn R
authors.initials: ER
authors.lastname: Riedel
authors.forename: Donato
authors.initials: D
authors.lastname: Nitti
authors.forename: W Douglas
authors.initials: WD
authors.lastname: Wong
authors.forename: Salvatore
authors.initials: S
authors.lastname: Pucciarelli
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D016190:Carboplatin / Q000008:administration & dosage; D002945:Cisplatin / Q000008:administration & dosage; D003131:Combined Modality Therapy; D019160:Endosonography; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005720:Gamma Rays; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008198:Lymph Nodes / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*
chemical_list: D016190:Carboplatin; D002945:Cisplatin; D002955:Leucovorin; D005472:Fluorouracil