619PDINTERIM RESULTS OF A RANDOMIZED CONTROLLED PHASE III TRIAL OF ELECTIVE NODAL IRRADIATION PLUS ERLOTINIB COMBINED WITH CHEMOTHERAPY FOR ESOPHAGEAL SQUAMOUS CELL CARCINOMA (NCT00686114).

ABSTRACT Aim: Concurrent chemoradiotherapy is the standard treatment for unresectable esophageal squamous cell carcinoma (SCC). This phase III trial was designed to determine whether the addition of elective nodal irradiation (ENI) and/or erlotinib to concurrent conventional chemoradiotherapy containing cisplatin/paclitaxel (CP) improved survival. Methods: This study was a 2x2 factorial design, with erlotinib and ENI as factors. Chinese patients with esophageal SCC were randomized to: (A) ENI/concurrent CP/erlotinib; (B) ENI/concurrent CP; (C) conventional-field irradiation (CFI)/concurrent CP/erlotinib; (D) CFI/concurrent CP. The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival, local-regional failure rate, and toxicity. Interim analysis was planned when 100 deaths were observed. NCT00686114. Results: At the interim analysis, 195 patients were recruited and 104 death events occurred. Median follow-up was 18.7 months (95% CI, 12.5 to 24.8) for all patients and 23.9 months for patients alive at last contact. There were no significant interactions between the two factors of ENI and erlotinib. Median OS was 33.5 months for ENI-treated patients (A + B) versus 15.3 months for CFI-treated patients (C + D; HR, 0.62; 95% CI, 0.42 to 0.92; P = .02). Median OS was 20.0 months for erlotinib-treated patients (A + C) versus 17.8 months for control patients (B + D; HR, 0.85; 95% CI, 0.57 to 1.25; P = .37). Patients treated with ENI plus erlotinib (A) achieved a 2-year survival rate of 61.6% and a median survival of 40.2 months. Hematologic toxicities grade ≥3 were the most common adverse events. Erlotinib was associated with a higher rate of all-grade rash events. Conclusions: This interim analysis shows an obvious tread toward benefits from ENI, and the addition of erlotinib to ENI combined with concurrent chemotherapy further prolongs OS in patients with oesophageal SCC. However, the results with respect to the value of ENI or erlotinib alone were not decisive; final OS analysis is estimated for late 2015. Disclosure: All authors have declared no conflicts of interest.