Phase III Study of Surgery Versus Definitive Concurrent Chemoradiotherapy Boost in Patients With Resectable Stage IIIA(N2) and Selected IIIB Non–Small-Cell Lung Cancer After Induction Chemotherapy and Concurrent Chemoradiotherapy (ESPATUE)

Purpose Concurrent chemoradiotherapy with or without surgery are options for stage IIIA(N2) non–small-cell lung cancer. Our previous phase II study had shown the efficacy of induction chemotherapy followed by chemoradiotherapy and surgery in patients with IIIA(N2) disease and with selected IIIB disease. Here, we compared surgery with definitive chemoradiotherapy in resectable stage III disease after induction. Patients and Methods Patients with pathologically proven IIIA(N2) and selected patients with IIIB disease that had medical/functional operability received induction chemotherapy, which consisted of three cycles of cisplatin 50 mg/m 2 on days 1 and 8 and paclitaxel 175 mg/m 2 on day 1 every 21 days, as well as concurrent chemoradiotherapy to 45 Gy given as 1.5 Gy twice daily, concurrent cisplatin 50 mg/m 2 on days 2 and 9, and concurrent vinorelbine 20 mg/m 2 on days 2 and 9. Those patients whose tumors were reevaluated and deemed resectable in the last week of radiotherapy were randomly assigned to receive a chemoradiotherapy boost that was risk adapted to between 65 and 71 Gy in arm A or to undergo surgery (arm B). The primary end point was overall survival (OS). Results After 246 of 500 planned patients were enrolled, the trial was closed after the second scheduled interim analysis because of slow accrual and the end of funding, which left the study underpowered relative to its primary study end point. Seventy-five patients had stage IIIA disease and 171 had stage IIIB disease according to the Union for International Cancer Control TNM classification, sixth edition. The median age was 59 years (range, 33 to 74 years). After induction, 161 (65.4%) of 246 patients with resectable tumors were randomly assigned; strata were tumor-node group, prophylactic cranial irradiation policy, and region. Patient characteristics were balanced between arms, in which 81 were assigned to surgery and 80 were assigned to a chemoradiotherapy boost. In arm B, 81% underwent R0 resection. With a median follow-up after random assignment of 78 months, 5-year OS and progression-free survival (PFS) did not differ between arms. Results were OS rates of 44% for arm B and 40% for arm A (log-rank P = .34) and PFS rates of 32% for arm B and 35% for arm A (log-rank P = .75). OS at 5 years was 34.1% (95% CI, 27.6% to 40.8%) in all 246 patients, and 216 patients (87.8%) received definitive local treatment. Conclusion The 5-year OS and PFS rates in randomly assigned patients with resectable stage III non–small-cell lung cancer were excellent with both treatments. Both are acceptable strategies for this good-prognosis group.