Background: NEOSCOPE compared toxicity and efficacy of 2 pre-op CRT regimens. Methods: Eligibility: Resectable ACA of the oesophagus/GOJ ≥ T3 and/or ≥ N1. Randomisation: 1:1 to OXCAP-CRT (oxaliplatin 85 mg/m2 Day 1,15,29; capecitabine 625 mg/m2 bd on days of RT) or CarPac-CRT (Carboplatin AUC2; paclitaxel 50 mg/m2 Day 1,8,15,22,29); concurrent RT: 45Gy/25 fractions/5 weeks. Both arms received induction chemo: 2 cycles of OXCAP (oxaliplatin 130 mg/m2 D1, Cape 625 mg/m²D1-21, q 3wk). Surgery: 6-8 weeks after naCRT. Detailed RT and pathology quality assurance was built into the protocol. Primary end-point: pathological complete response (pCR). Secondary: toxicity, surgical morbidity/mortality, R1 rate, OS. Statistics: A pCR of 15% would not warrant further investigation but a pCR of 35% would. 76 patients (38/arm) gave 90% power and one-sided type I error of 10% meaning that either arm having ≥10 pCR out of first 38 patients would be considered for Phase III. 85 patients to be recruited (allows 10% loss to follow up). Results: 85 patients were randomised between Oct 2013 and Feb 2015 from 17 UK centres. Patient characteristics: median age 65 yrs, Male (81%), WHO PS 0 (85%). Tumour characteristics: T3 (86%), N1 (48%), lower third/GOJ (90%), median tumour length 5.8cm. CTCAE grade 3/4 toxicity rate during CRT was OXCAP-CRT 42.1%, CarPac-CRT 52.4% (p=0.358). Protocol dose RT OXCAP-CRT 90.5%, CarPac-CRT 93%. Conclusion:Both regimens were well tolerated. CarPac-CRT passed the criteria for taking forward to a phase III study but OXCAP-RT did not. Funding: Cancer Research UK (C44694/A14614), ClinicalTrials.gov: NCT01843829, coordinated by Wales Cancer Trials Unit. Clinical trial information: NCT01843829

*10 out of first 38 patients randomised to this arm.