Purpose To investigate the feasibility and activity of hyperfractionated radiation therapy (Hfx RT) and concurrent chemotherapy (CT) consisting of low-dose, daily carboplatin and paclitaxel in patients with stage III non-small-cell lung cancer (NSCLC). Patients and Methods Sixty-four patients started their treatment on day I with 30 mg/m(2) of paclitaxel administered by 1-hour infusion. Hfx RT began on day 2 using 1.3 Gy bid to a total dose of 67.6 Gy and concurrent low-dose daily CT consisting of 25 mg/m(2) of carboplatin and 10 mg/m(2) Of paclitaxel, both given Mondays to Fridays during RT course. Results Objective response rate was 83% and included complete response in 27 patients (42%) and partial response in 26 patients (41%). Ten patients (16%) had stable disease, whereas only one patient (2%) had progressive disease. The median survival time was 28 months, and 3- and 5-year survival rates were 37% and 26%, respectively. The median time to local progression was 26 months, and 3- and 5-year local progression-free survival rates were 37% and 33%, respectively. The median time to distant metastasis was 25 months, and 3- and 5-year distant metastasis-free survival rates were 37% and 31%, respectively. Acute high-grade (greater than or equal to grade 3) toxicity was hematologic (25%), esophageal (17%), bronchopulmonary (13%), and skin (9%). Late high-grade toxicity was infrequent. Conclusion This combined Hfx RT/TC regimen produced results that are among the best ever reported and warrants further study in a prospective randomized fashion. (C) 2005 by American Society of Clinical Oncology.