Phase I study of stereotactic radiosurgery in patients with locally advanced pancreatic cancer

To determine the feasibility and toxicity of delivering stereotactic radiosurgery to patients with locally advanced pancreatic cancer. Patients with Eastern Cooperative Oncology Group performance status ≤2 and locally advanced pancreatic cancer were enrolled on this Phase I dose escalation study. Patients received a single fraction of radiosurgery consisting of either 15 Gy, 20 Gy, or 25 Gy to the primary tumor. Acute gastrointestinal toxicity was scored according to the Radiation Therapy Oncology Group criteria. Response to treatment was determined by serial high-resolution computed tomography scanning. Fifteen patients were treated at 3 dose levels (3 patients received 15 Gy, 5 patients received 20 Gy, and 7 patients received 25 Gy). At these doses, no Grade 3 or higher acute gastrointestinal toxicity was observed. This trial was stopped before any dose-limiting toxicity was reached, because the clinical objective of local control was achieved in all 6 evaluable patients treated at 25 Gy. It is feasible to deliver stereotactic radiosurgery to patients with locally advanced pancreatic cancer. The recommended dose to achieve local control without significant acute gastrointestinal toxicity is 25 Gy.