Chronicle: results of a randomised phase III trial in locally advanced rectal cancer after neoadjuvant chemoradiation randomising postoperative adjuvant capecitabine plus oxaliplatin (XELOX) versus control.
BACKGROUND
In stage III colon cancer, oxaliplatin/5-fluorouracil (5-FU)-based adjuvant chemotherapy (FOLFOX) improves disease-free survival (DFS) and overall survival (OS). In rectal adenocarcinoma following neoadjuvant chemoradiation (CRT), we examined the benefit of postoperative adjuvant capecitabine and oxaliplatin (XELOX) chemotherapy.


METHODS
Eligible patients were randomly assigned following fluoropyrimidine-based CRT and curative resection to observation or six cycles of XELOX. The primary end point was DFS; secondary end points were acute toxicity and OS. 390 patients were required in each arm, to detect an improvement in 3-year DFS from 40% to 50.5%, with 85% power and two-sided 5% significance level.


RESULTS
The study closed prematurely in 2008 because of poor accrual. Only 113 patients were randomly assigned to either observation (n = 59) or XELOX (n = 54). Compliance was poor, 93% allocated chemotherapy started and 48% completed six cycles. Protocolised dose reductions in XELOX were 39%, and levels of G3/G4 toxicity 40%. After a median follow-up of 44.8 months, 16 patients (27%) in the observation arm had relapsed or died compared with 12 patients (22%) in XELOX. The 3-year DFS rate was 78% with XELOX and 71% with observation [hazard ratio (HR) for DFS = 0.80; 95% confidence interval (CI) 0.38-1.69; P = 0.56]. The 3-year OS for XELOX and observation were 89% and 88%, respectively (HR for OS = 1.18; 95% CI 0.43-3.26; P = 0.75).


CONCLUSIONS
The observed improvement in DFS for adjuvant XELOX and similar OS were not statistically significant, as expected given the small number of patients and consequent low power. Our findings support the need for trials that test the role of neoadjuvant chemotherapy.


BACKGROUND
NCT00427713.
Department of Medical Oncology, Mount Vernon Centre for Cancer Treatment, London. Electronic address: rob.glynnejones@nhs.net.
R
R
Glynne-Jones
CRUK & UCL Cancer Trials Centre, London.
N
N
Counsell
Leeds Institute of Molecular Medicine, University of Leeds, Leeds.
P
P
Quirke
Department of Colorectal Surgery, University of Oxford, Oxford.
N
N
Mortensen
Queen's Centre for Oncology and Haematology, Castle Hill Hospital, Hull, UK.
A
A
Maraveyas
CRUK & UCL Cancer Trials Centre, London.
H M
HM
Meadows
CRUK & UCL Cancer Trials Centre, London.
J
J
Ledermann
Leeds Institute of Molecular Medicine, University of Leeds, Leeds.
D
D
Sebag-Montefiore
D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000069287:Capecitabine; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives; D006801:Humans; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*
D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D003841:Deoxycytidine; D000069287:Capecitabine; D005472:Fluorouracil
adjuvant chemotherapy; capecitabine; metastatic disease; oxaliplatin; preoperative chemoradiation; rectal adenocarcinoma