title: EUS-guided fiducial placement for stereotactic body radiotherapy in locally advanced and recurrent pancreatic cancer.
abstract: BACKGROUND
  Stereotactic body radiotherapy (SBRT) has been approved for the treatment of locally advanced pancreatic cancer. Placement of gold fiducials is required for real-time tracking and delivery of a high-dose therapeutic beam of radiation to the tumor. Traditionally, fiducials have been placed either intraoperatively or percutaneously. Recently, EUS-guided fiducial placement has been reported, but the safety and feasibility of this approach is not well defined.
  
  
  OBJECTIVE
  The aim of this study was to determine the safety, feasibility, and limitations of EUS-guided placement of 0.8 x 5.0 mm fiducials via a 19-gauge needle for locally advanced and recurrent pancreatic cancer.
  
  
  METHODS
  Prospective study of patients with either locally advanced or recurrent pancreatic cancer referred for EUS-guided fiducial placement for SBRT at our institution over a 3-year period.
  
  
  METHODS
  Tertiary referral center conducting >1800 EUS procedures annually.
  
  
  METHODS
  Primary outcome measurements included success, complications, and technical limitations of EUS-guided fiducial placement in pancreatic cancer. In addition, the percentage of patients successfully completing SBRT after EUS-guided fiducial placement was determined.
  
  
  RESULTS
  A total of 51 patients (mean age 73 years; 57% male) with locally advanced (n = 36) and recurrent (n = 15) pancreatic cancer were referred for EUS-guided fiducial placement. Fiducials were successfully placed in 46 patients (90%), with technical failures occurring in 4 patients (8%) with recurrent cancer after pancreaticoduodenectomy. In 3 patients (7%), the fiducials spontaneously migrated from the original site of injection, thereby requiring a second EUS procedure for placement of additional fiducials. Of the 46 patients with fiducials placed under EUS guidance, 42 patients (91%) successfully completed SBRT. Two patients experienced disease progression before SBRT, 1 patient was lost to follow-up, and 1 patient experienced a complication at ERCP that precluded further therapy. Only 1 complication (2%), of mild pancreatitis, occurred in a patient undergoing simultaneous placement of fiducials and celiac plexus neurolysis for intractable abdominal pain.
  
  
  CONCLUSIONS
  Single-center experience and lack of a formal follow-up protocol to assess for complications.
  
  
  CONCLUSIONS
  EUS-guided fiducial placement for SBRT in locally advanced and recurrent pancreatic cancer is safe and feasible. Successful placement was achieved in 90% of patients, with a low complication rate (2%). Furthermore, 91% of patients successfully completed SBRT after EUS-guided fiducial delivery. Although fiducials can spontaneously migrate from the initial injection site, the rate of migration is relatively low (7%), and no migration-related complications occurred over the course of this study. Limitations to EUS-guided fiducial placement may include surgically altered anatomy (pancreaticoduodenectomy) in patients with recurrent pancreatic cancer.
authors.affiliation: Division of Gastroenterology, Hepatology, and Nutrition, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. mks28@pitt.edu
authors.forename: Michael K
authors.initials: MK
authors.lastname: Sanders
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moser
authors.forename: Asif
authors.initials: A
authors.lastname: Khalid
authors.forename: Kenneth E
authors.initials: KE
authors.lastname: Fasanella
authors.forename: Herbert J
authors.initials: HJ
authors.lastname: Zeh
authors.forename: Steven
authors.initials: S
authors.lastname: Burton
authors.forename: Kevin
authors.initials: K
authors.lastname: McGrath
mesh_terms: D000368:Aged; D018450:Disease Progression; D019160:Endosonography / Q000379:methods*; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009339:Needles; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000601:surgery*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D011446:Prospective Studies; D016634:Radiosurgery / Q000295:instrumentation*; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome