title: Robotic stereotactic body radiation therapy for liver-limited malignant tumors.
abstract: BACKGROUND
  Stereotactic body radiotherapy (SBRT) is rapidly gaining favor as a new treatment modality for malignant liver tumors. Most of the studies have recruited patients with disseminated disease originating from the liver. This study focuses on disease limited to the liver.
  
  
  OBJECTIVE
  To perform a retrospective analysis of all patients with liver tumors treated by robotic stereotactic body radiation therapy in a single center.
  
  
  METHODS
  The study included 13 patients with 22 lesions. The inclusion criteria were: patients with 1-4 inoperable liver lesions and absence of any extrahepatic disease. All but 3 patients received 3 fractions delivered by the Cyberknife system of a total of 45 grey (Gy). The other 3 patients received 30 Gy.
  
  
  RESULTS
  The median follow-up time was 10.8 months (range: 7-16). The median dose was 41.5 Gy (range: 30-45). One lesion regressed (8%). In 5 patients, the disease was locally stabilized (38%), and in 7 other patients progression occurred (54%). Twelve patients (92%) are still alive, and 1 patient (8%) died. In 1 patient a new cancer (leukemia) was diagnosed.
  
  
  CONCLUSIONS
  The SBRT is well tolerated and effective for local control of most liver malignant tumors. It appears that SBRT is best suited for those patients in whom systemic recurrence can be controlled by chemotherapy. Further studies are mandatory to elucidate these effects on tumors of varying histology and to elaborate upon criteria used to select patients who can benefit most from this treatment.
authors.affiliation: Department of General, Transplant and Liver Surgery, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Frączek
authors.affiliation: Department of General, Oncology and Gastrointestinal Surgery, St. Anna Memorial Hospital, Warsaw, Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Sobocki
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Pędziwiatr
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Edward
authors.initials: E
authors.lastname: Skrocki
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Norbert
authors.initials: N
authors.lastname: Piotrkowicz
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Dobromira
authors.initials: D
authors.lastname: Tyc-Szczepaniak
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Korab-Chrzanowska
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Hevelke
authors.affiliation: Department of General, Transplant and Liver Surgery, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Krasnodębski
authors.affiliation: Institute of CyberSurgery, Wieliszew, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Koszewski
keywords: cyberknife; liver tumors; stereotactic body radiotherapy