title: Radiosurgery of liver tumors: value of robotic radiosurgical device to treat liver tumors.
abstract: BACKGROUND
  The treatment of isolated liver metastases has become a rapidly developing field with many new, technically advanced methods. Here we present the therapeutic efficacy of a robotic radiosurgery for local control of liver metastases from solid tumors.
  
  
  METHODS
  Patients with tumorous lesions to the liver, not qualifying for surgery, were treated with single-session radiosurgery (24 Gy) that used robotic image-guided real-time tumor tracking. All detectable lesions had to be irradiated. In a prospective analysis, follow-up was performed by magnetic resonance imaging scanning 2 months after the treatment, and subsequently at 3-month intervals to evaluate local control. For inclusion into the radiosurgery treatment protocol, tumor volumes had to be <90 ml.
  
  
  RESULTS
  Thirty-six patients (median age, 65 years) with a total of 54 target lesions were evaluated. Single lesions were treated in 23 patients and multiple targets in 13 patients. Metastases originated from colon cancer (n = 19), ovarian cancer (n = 3), pancreatic cancer (n = 2), breast cancer (n = 2), and others (n = 6). Four lesions were of primary liver origin (hepatocellular carcinoma and cholangiocellular carcinoma). Median tumor volume was 18 ml (range, 2.2-90 ml). The median follow-up was 21.3 months. The disease of 25 patients (69.4%) showed complete or partial local response, 6 patients (16.7%) had stable lesions, and 5 patients (14%) experienced local recurrence. Grade 2-4 adverse events due to radiation treatment were not observed.
  
  
  CONCLUSIONS
  Robotic radiosurgery with image-guided real-time tumor tracking of liver neoplasm is a new and promising approach for patients with disease that is not eligible for surgical resection and might enhance the possibilities of multidisciplinary oncological treatment concepts.
authors.affiliation: Department of Hematology and Oncology, University Hospital Grosshadern, LMU Munich, Munich, Germany. sebastian.stintzing@med.uni-muenchen.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Stintzing
authors.forename: Ralf-Thorsten
authors.initials: RT
authors.lastname: Hoffmann
authors.forename: Volker
authors.initials: V
authors.lastname: Heinemann
authors.forename: Markus
authors.initials: M
authors.lastname: Kufeld
authors.forename: Markus
authors.initials: M
authors.lastname: Rentsch
authors.forename: Alexander
authors.initials: A
authors.lastname: Muacevic
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016634:Radiosurgery; D012371:Robotics; D016019:Survival Analysis; D016896:Treatment Outcome