title: Robotic Stereotactic Body Radiation Therapy in Patients With Recurrent or Metastatic Abdominopelvic Tumors: A Single Institute Experience.
abstract: BACKGROUND
  The aim of this study was to evaluate the efficacy and toxicity of robotic CyberKnife (Accuray Incorporated, Sunnyvale, California)-based stereotactic body radiation therapy (SBRT) in patients with recurrent or metastatic abdominopelvic tumors.
  
  
  METHODS
  A total of 69 patients treated between May 2008 and January 2011 were evaluated retrospectively. Indication for SBRT was persistent disease in 3 (4%) patients, local recurrence in 29 (42%) patients, regional recurrence in 13 (19%) patients, and oligometastatic disease in 24 (35%) patients. Forty-two (61%) patients were previously irradiated to the same region and 27 (39%) patients were treated for the first time. The median age was 59 years (range, 24-86 years). There were 31 (45%) male and 38 (55%) female patients. The median total dose was 30 Gy (range, 15-60 Gy) delivered with a median 3 fractions (range, 2-5 fractions). The tumor response to treatment was assessed by computed tomography, magnetic resonance imaging, or positron emission tomography.
  
  
  RESULTS
  At the 12-month (range, 2-44 months) median follow-up, local control was 65% and median overall survival (OS) was 20 months. A larger gross tumor volume (≥ 67 cm(3)) was significantly correlated with worse 1-year OS (81% vs 48%, P = .03). The patients with local recurrence occurring <11 months had a significantly shorter 1-year local control rate than patients with ≥ 11 months (31% vs 91%, P < .001). Grade 3-4 acute and late toxicities were seen in 7% and 15% of patients, respectively. The patients with previous radiotherapy history had significantly higher rate of acute toxicity (19% vs 0%, P = .019). Late toxicity was significantly higher in pelvic tumors than in abdominal tumors (3% vs 28%, P = .004).
  
  
  CONCLUSIONS
  The SBRT seems to be feasible and resulted in good treatment outcomes in patients with recurrent or metastatic abdominopelvic tumors.
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: D
authors: D
authors: Sezen
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: M
authors: M
authors: Gurkaynak
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: M
authors: M
authors: Gultekin
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: M
authors: M
authors: Cengiz
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: F
authors: F
authors: Yildiz
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: F
authors: F
authors: Zorlu
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: F
authors: F
authors: Akyol
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: G
authors: G
authors: Yazici
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors: P
authors: P
authors: Hurmuz
authors: Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey gozyigit@hacettepe.edu.tr.
authors: G
authors: G
authors: Ozyigit
mesh_terms: D000008:Abdominal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D010386:Pelvic Neoplasms / Q000601:surgery*; D016016:Proportional Hazards Models; D016634:Radiosurgery; D012189:Retrospective Studies; D012371:Robotics; D025321:Surgery, Computer-Assisted; D016896:Treatment Outcome; D055815:Young Adult
keywords: abdominopelvic tumors; metastases; recurrent tumor; stereotactic body radiation therapy