Chemoradiation for resected pancreatic adenocarcinoma with or without intraoperative radiation therapy boost:...

To analyze prognostic factors associated with long-term outcomes in patients with pancreatic cancer treated with chemoradiation therapy (CRT) and surgery with or without intraoperative electron beam radiotherapy (IOERT).

From January 1995 to December 2012, 60 patients with adenocarcinoma of the pancreas and locoregional disease (clinical stage IB [n = 13; 22%], IIA [n = 16; 27%], IIB [n = 22; 36%], IIIC [n = 9; 15%]) were treated with CRT (45-50.4 Gy before surgery [n = 19; 32%] and after surgery [n = 41; 68%]) and curative resection (R0 [n = 34; 57%], R1 [n = 26, 43%]). Twenty-nine patients (48%) also received a pre-anastomosis IOERT boost (applicator diameter size, 7-10 cm; dose, 10-15 Gy; beam energy, 9-18 MeV).

With a median follow-up of 15.9 months (range, 1-182), 5-year overall survival (OS), disease-free survival (DFS), and locoregional control were 20%, 13%, and 58%, respectively. Univariate analyses showed that R1 margin resection status (HR, 3.17; p = 0.04), not receiving IOERT (HR, 7.33; p = 0.01), and postoperative CRT (HR, 5.12; p = 0.04) were associated with a higher risk of locoregional recurrence. In the multivariate analysis, only margin resection status (HR, 3.0; p = 0.05) and not receiving IOERT (HR, 6.75; p = 0.01) retained significance with regard to locoregional recurrence. Postoperative mortality and perioperative complications were 3% (n = 2) and 43% (n = 26).

Although local control is good in the radiation-boosted area, OS remains modest owing to high risk of distant metastases. Intensified locoregional treatment needs to be tested in the context of more efficient systemic therapy.