VERO® radiotherapy for low burden cancer: 789 patients with 957 lesions.

ABSTRACT

PURPOSE: 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.