title: Stereotactic Body Radiation Therapy for Locally Advanced Pancreatic Cancer: A Systematic Review and Pooled Analysis of 19 Trials.
abstract: Although surgery is the standard of care for resectable pancreatic cancer (PC), standard-dose chemoradiation therapy and chemotherapy alone are suitable for patients with unresectable disease. Stereotactic body radiation therapy (SBRT) is an alternative, focused local therapy that delivers high radiation doses within a few fractions to the cancer, sparing the surrounding critical tissue. We performed a systematic review and pooled analysis of published trials to evaluate the efficacy and safety of this emerging treatment modality.
  
  
  
  We searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, SCOPUS, the Web of Science, and CINAHL for publications regarding SBRT for locally advanced PC. The 1-year overall survival (OS) rate was the primary endpoint, and the median OS, 2-year OS rate, 1-year locoregional control (LRC) rate, and grade 3 to 4 toxicities were the secondary endpoints. A multivariate random-effects meta-analysis was performed to calculate the aggregated OS rates at 1 and 2 years and the 1-year LRC rate.
  
  
  
  A total of 19 studies, encompassing 1009 patients, were included in the present analysis. The pooled 1-year OS was 51.6% in 13 trials with data available. The median OS ranged from 5.7 to 47 months (median 17). The LRC rate at 1 year was 72.3%. Overall, the occurrence of severe adverse events did not exceed 10%. LRC appeared to correlate with the total SBRT dose and the number of fractions.
  
  
  
  The advantages of SBRT in terms of treatment time, satisfactory OS, and LRC indicate that it is an effective option for inoperable PC. However, a definitive validation of this treatment modality in large randomized studies is required, owing to the nonrandomized nature of the included studies and the limitations of small single-center series that include mixed populations.
authors.affiliation: Oncology Unit, Department of Oncology, ASST Bergamo Ovest, Treviglio, Italy. Electronic address: faupe@libero.it.
authors.forename: Fausto
authors.initials: F
authors.lastname: Petrelli
authors.affiliation: Department of Radiosurgery and Radiotherapy, Istituto Clinico Humanitas Cancer Center and Research Hospital, Milan, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Comito
authors.affiliation: Oncology Unit, Igea Hospital, Milan, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ghidini
authors.affiliation: Department of Biomedical Sciences, Humanitas University and Radiotherapy and Radiosurgery Department-Humanitas Research Hospital, Milan, Italy.
authors.forename: Valter
authors.initials: V
authors.lastname: Torri
authors.affiliation: Department of Radiosurgery and Radiotherapy, Istituto Clinico Humanitas Cancer Center and Research Hospital, Milan, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Scorsetti
authors.affiliation: Oncology Unit, Department of Oncology, ASST Bergamo Ovest, Treviglio, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Barni
mesh_terms: D021441:Carcinoma, Pancreatic Ductal / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy*; D006801:Humans; D015999:Multivariate Analysis; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000532:radiotherapy*; D011446:Prospective Studies; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors