In this phase 1 study, 45 patients with stage IV NSCLC and symptomatic central primary tumors were treated with a cyclical Quad Shot regimen to assess response and tolerability. Each cycle of palliative RT consisted of 14.8 Gy in 4 BID fractions over two days. The trial used a dose-escalation design to test multiple cycles of Quad Shot at 3-4 week intervals. In the 2 cycle cohort, there was one dose limiting event of grade 3 esophagitis after cycle 1. In the 3 cycle cohort, there were no dose limiting events. No patients had a delay in their systemic therapy. The rate of grade 2 esophagitis was 12%. The majority of patients had symptom response. | Zhang, Int J Radiat Oncol Biol Phys 2026
