1. Department of Medical Oncology, Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru
2. Faculty of Medicine, Universidad Peruana San Juan Bautista, Lima, Peru
3. Department of Research, Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru
4. Department of Pathology, Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru
5. Department of Neurosurgery, Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru