title: Comparative survival effectiveness between pre-operative and postoperative chemoradiotherapy for locally advanced rectal cancer: a retrospective study in Phramongkutklao Hospital.
abstract: BACKGROUND
  In earlier years, postoperative chemoradiotherapy was a recommended standard treatment for locally advanced rectal cancer Based on several clinical trials, the pre-operative approach was then considered afavorable optimal time to deliver the treatment due to significant improvement in local tumor control. Given that, both pre-operative and postoperative approaches were performed in Phramongkutklao Hospital.
  
  
  OBJECTIVE
  This study compared 2-year disease-free survival (DFS) between pre-operative and postoperative chemoradiotherapy in locally advanced rectal cancer.
  
  
  METHODS
  A retrospective study was conducted in 78patients with clinical stage T3, T4 or node-positive disease who had received either pre-operative or postoperative concurrent chemoradiation that was carried out between 2004 and 2008. The combined multimodality approach consisted of Fluorouracil (5-FU) based chemotherapy and a long course of radiation therapy. After the last session of chemoradiotherapy in the pre-operative group, surgery was performed 4-6 weeks later followed by remaining cycles ofchemotherapy whereas the postoperative group began chemoradiotherapy 4-6 weeks after surgery. The primary endpoint was 2-year disease-free survival (DFS).
  
  
  RESULTS
  Of the eligible 78 patients, 19 patients (9 pre-operative, 10 postoperative) had recurrence during the first two years after completion ofradiotherapy by which the first event of recurrence was classified as either local recurrence only, distant metastasis only, or both local and distant recurrence. The 2-year DFS between these two groups was not statistically diferent (78.6% pre-operative vs. 72.2% postoperative, p = 0.521), however, the pre-operative, concurrent chemoradiotherapy provided a possible DFS benefit. No statistical difference in overall toxic events between the two treatment groups; however, there is a tendency to develop more toxicity in thepostoperative group.
  
  
  CONCLUSIONS
  No significant statistical difference in 2-year DFS between the pre-operative andpostoperative but possible DFS benefit was suggested in pre-operative group.
authors.forename: Pyada
authors.initials: P
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic; D059248:Chemoradiotherapy; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006761:Hospitals; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D011182:Postoperative Care; D011184:Postoperative Period; D011300:Preoperative Care; D012004:Rectal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D012189:Retrospective Studies; D013785:Thailand
chemical_list: D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil