SCOPE 1: A phase II/III trial of chemoradiotherapy in esophageal cancer plus or minus cetuximab

LBA3 Background: SCOPE 1 is the largest multicentre trial of definitive chemo-radiotherapy (dCRT) in localised oesophageal cancer (LOC) in the UK and investigated adding cetuximab to standard cisplatin and fluoropyrimidine treatment. Methods: Patients in this phase II/III trial had LOC and been selected to receive dCRT and were randomised to receive cisplatin 60mg/m2 D1 and capecitabine 625mg/m2 daily D1-21 for 4 cycles, cycles 3 and 4 given concurrently with 50Gy in 25 fractions of RT with or without cetuximab 400mg/m2 D1 followed by 250mg/m2weekly. Recruitment continued from 02/2008 until analysis of the phase II endpoint (24 week failure free survival in the cetuximab arm, overall sample size 180: p1=0.60 and p2=0.75, α=0.05, β=0.9) in 01/2012. The phase II endpoint was not met and the IDMC recommended trial closure on the basis of futility. Results: 258 patients were recruited. Median age 67; morphology(%) SCC:ACA 73:27; tumour location(%) upper:middle:lower 11:45:44; stage(%) I:II:III 3:37:60; reason not for surgery(%) disease extent:patient choice:comorbidity 47:38:16. Patients who received cetuximab had: higher non-haematologic toxicity (78 vs 62.8%, p=0.004; primarily dermatological (22 vs 4%) and metabolic (24% vs 11%)); a lower rate of completion of standard therapy (capecitabine 69 vs 85%, p=0.002; cisplatin 77 vs 90%, p=0.005 and radiotherapy (75 vs 86%, p=0.027); reduced failure free survival at 24 weeks (66 vs 77%), median survival (22 vs 25 months, log rank p=0.043) and 2-yr survival (41 vs 56%). Conclusions: In SCOPE 1, disease control and survival in the standard dCRT arm is superior to any previous published multi-centre studies. The use of cetuximab was associated with greater toxicity, lower doses of dCRT and worse survival. Cetuximab cannot be recommended in combination with standard dCRT for unselected patients with oesophageal cancer. Strategies to build on these results should incorporate biomarker driven treatment and latest radiotherapy technologies to safely intensify treatment. This trial was sponsored by Velindre NHS Trust, conducted by Wales Cancer Trials Unit at Cardiff University and supported by CR-UK [grant number C20177/A7256]. Clinical trial information: 47718479.