title: Comparison of two preoperative chemoradiotherapy regimens for locally advanced rectal cancer: capecitabine alone versus capecitabine plus irinotecan.
abstract: BACKGROUND
  To compare the short-term tumor response and long-term clinical outcome of two preoperative chemoradiotherapy (CRT) regimens for locally advanced rectal cancer.
  
  
  METHODS
  This study included 231 patients scheduled for preoperative CRT using two chemotherapeutic protocols from April 2003-August 2006. Pelvic radiotherapy (50.4 Gy) was delivered concurrently with capecitabine (n = 148) or capecitabine/irinotecan (n = 83). Surgery was performed 4-8 weeks after CRT completion. Tumor responses to CRT were assessed using both radiologic and pathologic measurements. Radiologic responses were evaluated by magnetic resonance volumetry, which was performed at the initial work-up and after completion of preoperative CRT just before surgery. Pathologic responses were assessed with downstaging (ypStage 0-1) and grading tumor regression. Clinical outcomes were evaluated in terms of local control, relapse-free survival, and overall survival rates.
  
  
  RESULTS
  Radiologic examination demonstrated that tumor volume decreased by 65.6% in the capecitabine group and 66.8% capecitabine/irinotecan group (p = 0.731). Postoperative pathologic stage determination showed that tumor downstaging occurred in 44.1% of the capecitabine group and 48.6% of the capecitabine/irinotecan group (p = 0.538). The sum of tumor regression grade 3 (near complete response) and 4 (complete response) after CRT were 28.6% in the capecitabine group and 37.5% in the capecitabine/irinotecan group (p = 0.247). There were no significant differences between the two groups in 5-year local control (91.7% vs. 92.5%; p = 0.875), relapse-free survival (80.8% vs. 77.2%; p = 0.685), and overall survival (88.4% vs. 90.4%; p = 0.723).
  
  
  CONCLUSIONS
  This study revealed no differences in the short-term tumor response and long-term clinical outcome between preoperative capecitabine and capecitabine/irinotecan CRT regimens for locally advanced rectal cancer.
authors.forename: Sung Uk
authors.initials: SU
authors.lastname: Lee
authors.affiliation: Proton Therapy Center, Goyang, Republic of Korea. radiopiakim@hanmail.net.
authors.forename: Dae Yong
authors.initials: DY
authors.lastname: Kim
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Baek
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Chang
authors.forename: Min Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Park
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Oh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000737:chemistry*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives*; D000069287:Capecitabine; D059248:Chemoradiotherapy / Q000379:methods; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives*; D005500:Follow-Up Studies; D006801:Humans; D000077146:Irinotecan; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011184:Postoperative Period; D057234:Preoperative Period; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy* / Q000601:surgery; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D003841:Deoxycytidine; D000069287:Capecitabine; D000077146:Irinotecan; D005472:Fluorouracil; D002166:Camptothecin