1. Radiation Oncology and Research Unit, Las Palmas (Canary Islands), Spain
2. Canary Islands Institute for Cancer Research (ICIC), Las Palmas (Canary Islands), Spain
3. Medical Physics, Las Palmas (Canary Islands), Spain
4. La Paterna Medical Center, Las Palmas (Canary Islands), Spain
5. Chronic Pain Unit, Dr Negrín Hospital, Las Palmas (Canary Islands), Spain