title: Stereotactic body radiation therapy for locally advanced and borderline resectable pancreatic cancer is effective and well tolerated.
abstract: OBJECTIVE
  Stereotactic body radiation therapy (SBRT) provides high rates of local control (LC) and margin-negative (R0) resections for locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC), respectively, with minimal toxicity.
  
  
  METHODS
  A single-institution retrospective review was performed for patients with nonmetastatic pancreatic cancer treated with induction chemotherapy followed by SBRT. SBRT was delivered over 5 consecutive fractions using a dose painting technique including 7-10 Gy/fraction to the region of vessel abutment or encasement and 5-6 Gy/fraction to the remainder of the tumor. Restaging scans were performed at 4 weeks, and resectable patients were considered for resection. The primary endpoints were overall survival (OS) and progression-free survival (PFS).
  
  
  RESULTS
  Seventy-three patients were evaluated, with a median follow-up time of 10.5 months. Median doses of 35 Gy and 25 Gy were delivered to the region of vessel involvement and the remainder of the tumor, respectively. Thirty-two BRPC patients (56.1%) underwent surgery, with 31 undergoing an R0 resection (96.9%). The median OS, 1-year OS, median PFS, and 1-year PFS for BRPC versus LAPC patients was 16.4 months versus 15 months, 72.2% versus 68.1%, 9.7 versus 9.8 months, and 42.8% versus 41%, respectively (all P>.10). BRPC patients who underwent R0 resection had improved median OS (19.3 vs 12.3 months; P=.03), 1-year OS (84.2% vs 58.3%; P=.03), and 1-year PFS (56.5% vs 25.0%; P<.0001), respectively, compared with all nonsurgical patients. The 1-year LC in nonsurgical patients was 81%. We did not observe acute grade ≥3 toxicity, and late grade ≥3 toxicity was minimal (5.3%).
  
  
  CONCLUSIONS
  SBRT safely facilitates margin-negative resection in patients with BRPC pancreatic cancer while maintaining a high rate of LC in unresectable patients. These data support the expanded implementation of SBRT for pancreatic cancer.
authors.affiliation: Department of Radiation Oncology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Chuong
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Springett
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Freilich
authors.forename: Catherine K
authors.initials: CK
authors.lastname: Park
authors.forename: Jill M
authors.initials: JM
authors.lastname: Weber
authors.forename: Eric A
authors.initials: EA
authors.lastname: Mellon
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Hodul
authors.forename: Mokenge P
authors.initials: MP
authors.lastname: Malafa
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Meredith
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Hoffe
authors.forename: Ravi
authors.initials: R
authors.lastname: Shridhar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017024:Chemotherapy, Adjuvant / Q000379:methods; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005260:Female; D057918:Fiducial Markers; D056973:Four-Dimensional Computed Tomography; D006801:Humans; D060828:Induction Chemotherapy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016634:Radiosurgery / Q000379:methods* / Q000401:mortality; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies