Aim: To analyze retrospectively the results of postoperative external beam radiotherapy (EBRT) for resected pancreatic adenocarcinoma.
Patients and methods: The records of 47 patients treated with gross complete resection (R0: 24 patients, R1: 23 patients) and post-operative EBRT were reviewed. The median dose of EBRT was 50 Gy (range, 12-60 Gy), and chemotherapy was used in 37 patients (78.7%). The median follow-up period for all 47 patients was 14.4 months (range, 0.9-67.9 months).
Results: At the time of this analysis, 24 patients (51.1%) had disease recurrence. Local failure was observed in 10 patients (21.3%), and the 2-year local control (LC) rate in all patients was 68.7%. Patients treated with EBRT and chemotherapy had a significantly more favorable LC (2-year LC rate: 76.0%) than those treated with EBRT alone (2-year LC rate: 40%, p=0.0472). The median survival time and the 2-year actuarial overall survival (OS) in all 47 patients were 30.0 months and 54.5%, respectively. Patients treated with EBRT and chemotherapy had a significantly more favorable OS (2-year OS rate: 61.6%) than those treated with EBRT alone (2-year OS: 25.0%, p=0.0454). On univariate analysis, chemotherapy use alone had a significant impact on OS, and on multivariate analysis, chemotherapy use also was a significant prognostic factor. There were no late morbidities of NCI-CTC Grade 3 or greater.
Conclusion: Post-operative EBRT with chemotherapy yields a favorable LC rate for resected pancreatic adenocarcionoma, and EBRT combined with chemotherapy confers a survival benefit compared to EBRT alone.