The records of 210 patients treated with gross complete resection (R0: 147 patients; R1: 63 patients) and IORT with or without EBRT were reviewed. One hundred forty-seven patients (70.0 % ) were treated without EBRT and 114 patients (54.3 % ) were treated in conjunction with chemotherapy. The median doses of IORT and EBRT were 25 Gy (range, 20–30 Gy) and 45 Gy (range, 20–60Gy), respectively. The median follow-up of the surviving 62 patients was 26.3 months (range, 2.7–90.5 months).
At the time of this analysis, 150 of 210 patients (71.4 % ) had disease recurrences. Local failure was observed in 31 patients (14.8 % ), and the 2-year local control rate in all patients was 83.7 % . The median survival time and the 2-year actuarial overall survival (OS) in all 210 patients were 19.1 months and 42.1 % , respectively. Patients treated with IORT and chemotherapy had a significantly more favorable OS than those treated with IORT alone (p = 0.0011). On univariate analysis, chemotherapy use, degree of resection, carbohydrate antigen 19-9, and pathological N stage had a significant impact on OS and on multivariate analysis; these four factors were significant prognostic factors. Late gastrointestinal morbidity of NCI-CTC Grade 4 was observed in 7 patients (3.3 % ).
IORT yields an excellent local control rate for resected pancreatic cancer with few frequencies of severe late toxicity, and IORT combined with chemotherapy confers a survival benefit compared with that of IORT alone.