title: Preoperative short-course concurrent chemoradiation therapy followed by delayed surgery for locally advanced rectal cancer: a phase 2 multicenter study (KROG 10-01).
abstract: OBJECTIVE
  A prospective phase 2 multicenter trial was performed to investigate the efficacy and safety of preoperative short-course concurrent chemoradiation therapy (CRT) followed by delayed surgery for patients with locally advanced rectal cancer.
  
  
  METHODS
  Seventy-three patients with cT3-4 rectal cancer were enrolled. Radiation therapy of 25 Gy in 5 fractions was delivered over 5 consecutive days using helical tomotherapy. Concurrent chemotherapy was administered on the same 5 days with intravenous bolus injection of 5-fluorouracil (400 mg/m(2)/day) and leucovorin (20 mg/m(2)/day). After 4 to 8 weeks, total mesorectal excision was performed. The primary endpoint was the pathologic downstaging (ypStage 0-I) rate, and secondary endpoints included tumor regression grade, tumor volume reduction rate, and toxicity.
  
  
  RESULTS
  Seventy-one patients completed the planned preoperative CRT and surgery. Downstaging occurred in 20 (28.2%) patients, including 1 (1.4%) with a pathologic complete response. Favorable tumor regression (grade 4-3) was observed in 4 (5.6%) patients, and the mean tumor volume reduction rate was 62.5 ± 21.3%. Severe (grade ≥3) treatment toxicities were reported in 27 (38%) patients from CRT until 3 months after surgery.
  
  
  CONCLUSIONS
  Preoperative short-course concurrent CRT followed by delayed surgery for patients with locally advanced rectal cancer demonstrated poor pathologic responses compared with conventional long-course CRT, and it yielded considerable toxicities despite the use of an advanced radiation therapy technique.
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Seung-Gu
authors.initials: SG
authors.lastname: Yeo
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Oh
authors.forename: Dae Yong
authors.initials: DY
authors.lastname: Kim
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Baek
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Park
authors.forename: Min Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Chang
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Jang
authors.forename: Jun-Gi
authors.initials: JG
authors.lastname: Kim
authors.forename: Myung Ah
authors.initials: MA
authors.lastname: Lee
authors.forename: Taek-Keun
authors.initials: TK
authors.lastname: Nam
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D059248:Chemoradiotherapy / Q000009:adverse effects / Q000379:methods*; D019583:Dose Fractionation, Radiation; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012004:Rectal Neoplasms / Q000473:pathology / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D000964:Antimetabolites, Antineoplastic; D002955:Leucovorin; D005472:Fluorouracil