1. Neurosurgery Department, Instituto Nacional de Enfermedades Neoplasicas, Lima, 15038, Peru
2. Research Department, Instituto Nacional de Enfermedades Neoplasicas, Lima, 15038, Peru
3. Faculty of Medicine, Universidad Peruana San Juan Bautista, Lima, 15067, Peru
4. Pathology Department, Instituto Nacional de Enfermedades Neoplasicas, Lima, 15038, Peru
5. Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital, Columbus, OH, 43210, USA