title: VERO® radiotherapy for low burden cancer: 789 patients with 957 lesions.
abstract: OBJECTIVE
  The aim of this retrospective study is to evaluate patient profile, feasibility, and acute toxicity of RadioTherapy (RT) delivered by VERO® in the first 20 months of clinical activity.
  
  
  METHODS
  Inclusion criteria: 1) adult patients; 2) limited volume cancer (M0 or oligometastatic); 3) small extracranial lesions; 4) treatment between April 2012 and December 2013 and 5) written informed consent. Two techniques were employed: intensity modulated radiotherapy (IMRT) and stereotactic body radiotherapy (SBRT). Toxicity was evaluated using Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer (RTOG/EORTC) criteria.
  
  
  RESULTS
  Between April 2012 and December 2013, 789 consecutive patients (957 lesions) were treated. In 84% of them one lesion was treated and in 16% more than one lesion were treated synchronously/metachronously; first radiotherapy course in 85%, re-irradiation in 13%, and boost in 2% of cases. The treated region included pelvis 46%, thorax 38%, upper abdomen 15%, and neck 1%. Radiotherapy schedules included <5 and >5 fractions in 75% and 25% respectively. All patients completed the planned treatment and an acceptable acute toxicity was observed.
  
  
  CONCLUSIONS
  RT delivered by VERO® was administrated predominantly to thoracic and pelvic lesions (lung and urologic tumours) using hypofractionation. It is a feasible approach for limited burden cancer offering short and well accepted treatment with favourable acute toxicity profile. Further investigation including dose escalation and other available VERO® functionalities such as real-time dynamic tumour tracking is warranted in order to fully evaluate this innovative radiotherapy system.
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy; Department of Oncology and Haemato-oncology, University of Milan, Milan, Italy; Equally contributed to the article.
authors.forename: R
authors.initials: R
authors.lastname: Orecchia
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy; Equally contributed to the article; Affiliation at the time of the study.
authors.forename: A
authors.initials: A
authors.lastname: Surgo
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy; Affiliation at the time of the study.
authors.forename: M
authors.initials: M
authors.lastname: Muto
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Ferrari
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Piperno
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: M A
authors.initials: MA
authors.lastname: Gerardi
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Comi
authors.affiliation: Unit of Radiation Research, European Institute of Oncology, Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Garibaldi
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Ciardo
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Bazani
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Golino
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Pansini
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Fodor
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Romanelli
authors.affiliation: University of Milan, Milan, Italy; Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Maestri
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Scroffi
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Mazza
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy; Department of Oncology and Haemato-oncology, University of Milan, Milan, Italy.
authors.forename: B A
authors.initials: BA
authors.lastname: Jereczek-Fossa
keywords: IMRT; SBRT; VERO®-system; hypofractionation; low burden cancer