Stereotactic body radiotherapy (SBRT) for patients with locally advanced pancreatic cancer: A single center experience.

INTRODUCTION: Despite advances in treatment, notably in systemic therapy, the prognosis of pancreatic adenocarcinoma (PADC) remains dismal. Stereotactic body radiotherapy (SBRT) is an emerging tool in the complex management of PADC. We review outcomes of SBRT for PADC at our institution. METHODS: We reviewed patients treated with SBRT for either unresectable PADC or locally recurrent PADC after surgery. Treatment was delivered using a robotic radiosurgery system with respiratory tracking. The median prescribed dose was 30 Gy (30-35 Gy), delivered in 5-6 fractions. Toxicities were reported as per CTCAE v4.0. Survival was estimated using the Kaplan-Meier method. RESULTS: Between October 2010 and March 2016, 21 patients were treated at our institution. The median follow-up was 7 months (range: 1-28). The 1-year local control rate was 57%. The 1-year overall survival was 25% for locally advanced patients and 67% for those with local recurrences (p = 0.27). Eighty percent of cancer related deaths were due to metastatic progression. Five patients (24%) had Grade I-II gastrointestinal acute toxicity; one patient had fatal gastrointestinal bleeding 6 months after SBRT. CONCLUSION: In PADC, fractionated SBRT dose schedules near 30 Gy may strike the best balance of local control and bowel toxicity. More work is required to integrate pancreatic SBRT with modern systemic therapy.