Phase II study of bevacizumab with concurrent capecitabine and radiation followed by maintenance gemcitabine and bevacizumab for locally advanced pancreatic cancer: Radiation Therapy Oncology Group RTOG 0411.

PURPOSE

The primary objective of this study was to assess the 1-year survival of patients with locally advanced, unresectable pancreatic cancer treated with the combination of bevacizumab, capecitabine, and radiation. Secondary end points were toxicity, progression-free survival (PFS), and response rate (RR).

PATIENTS AND METHODS

Patients with locally advanced pancreatic cancer without duodenal invasion were treated with 50.4 Gy per 28 fractions to the gross tumor with concurrent capecitabine 825 mg/m(2) orally twice daily on days of radiation and bevacizumab 5 mg/kg on days 1, 15, and 29 followed by maintenance gemcitabine 1 g/m(2) weekly for 3 weeks and bevacizumab 5 mg/kg every 2 weeks, both in 4-week cycles until progression. Treatment plans were reviewed for quality assurance (QA).

RESULTS

Between January 2005 and February 2006, 82 eligible patients were treated. The median and 1-year survival rates were 11.9 months (95% CI, 9.9 to 14.0 months) and 47% (95% CI, 36% to 57%). Median PFS was 8.6 months (95% CI, 6.9 to 10.5), and RR was 26%. Overall, 35.4% of patients had grade 3 or greater treatment-related gastrointestinal toxicity (22.0% during chemoradiotherapy, 13.4% during maintenance chemotherapy). Unacceptable radiotherapy protocol deviations (ie, inappropriately generous volume contoured) correlated with grade 3 or greater gastrointestinal toxicity during chemoradiotherapy (45% v 18%; adjusted odds ratio, 3.7; 95% CI, 0.98 to 14.1; P = .05).

CONCLUSION

The addition of bevacizumab to chemoradiotherapy followed by bevacizumab and gemcitabine resulted in a similar median survival to previous Radiation Therapy Oncology Group studies in patients with locally advanced pancreatic cancer. Prospective QA may help limit toxicity in future trials.