title: Preoperative chemoradiation and IOERT for unresectable or borderline resectable pancreas cancer.
abstract: OBJECTIVE
  Pre-operative chemoradiation (preop CRT) plus intraoperative electron irradiation (IOERT) has been used in the multidisciplinary treatment for patients with locally advanced unresectable or borderline resectable pancreas cancer. This review was performed to evaluate survival, relapse patterns and prognostic factors in patients treated with curative intent.
  
  
  METHODS
  Between January 2002 and December 2010, 48 patients with locally advanced pancreatic ductal adenocarcinoma received preop CRT prior to an attempt at resection and IOERT. 31/48 (65%) patients proceeded to curative-intent surgical resection. Resection status prior to preop CRT was locally unresectable (20 patients) and borderline resectable (11 patients). Preop CRT (45-50.4 Gy/25-28 Fx in 27/31) was delivered with concurrent 5FU or gemcitabine-based regimens. Subsequent gross total resection was achieved in 16 patients (R0, 11; R1, 5). IOERT was delivered in 28 patients (dose, 10-20 Gy). 16 patients also received adjuvant post-operative systemic chemotherapy. Outcomes evaluated include survival, local failure in the EBRT field (LF), central failure in the IOERT field (CF), and distant metastases.
  
  
  RESULTS
  Resection status was predictive for survival and for patterns of relapse. For patients with at least a gross total resection after preop CRT (R0/R1; n=16) vs. no resection (n=15), both median and overall survival were improved (median 23 vs. 10 months; 2-year, 40% vs. 17%; 3-year, 40% vs. 0%; P=0.002). Liver or peritoneal relapse was documented in 22/31 patients (71%); LF/CF in 5/26 (16%).
  
  
  CONCLUSIONS
  Long term survival and disease control are achievable in select patients with borderline resectable or locally unresectable pancreas cancer when gross total surgical resection is achieved after preop CRT. Continued evaluation of curative-intent combined modality therapy is warranted in this high risk population, but additional strategies are needed to improve resectability and disease control.
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Cancer Center - Arizona (MCCC-A), Scottsdale/Phoenix, AZ, USA.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Ashman
authors.forename: Adyr A
authors.initials: AA
authors.lastname: Moss
authors.forename: William G
authors.initials: WG
authors.lastname: Rule
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Callister
authors.forename: K Sudhakar
authors.initials: KS
authors.lastname: Reddy
authors.forename: David C
authors.initials: DC
authors.lastname: Mulligan
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Collins
authors.forename: Giovanni
authors.initials: G
authors.lastname: De Petris
authors.forename: Leonard L
authors.initials: LL
authors.lastname: Gunderson
authors.forename: Mitesh
authors.initials: M
authors.lastname: Borad
keywords: Pancreatic neoplasms; chemotherapy; intraoperative procedures; radiotherapy; surgery