1. Department of Oncology, Oxford Cancer Center, Oxford University Hospitals NHS Foundation Trust, Churchill Hospital, OX3 7LE, Oxford, UK
2. Department of Oncology, University of Oxford, OX3 7ER, Oxford, UK
3. Post Graduation Program in Medicine, Faculty of Medicine, Nine of July University, 015250-000, São Paulo, Brazil
4. Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru
5. São Paulo Cancer Institute, University of São Paulo, São Paulo, 01246-000, Brazil