1. Lagos University Teaching Hospital, Lagos, Nigeria.
2. Surgery, Duke Medical Center, Durham, NC, U.S.A.
3. Department of Oncology, Beijing Cancer Hospital, Peking University School of Oncology, Beijing, China. Departments of Duke Medical Center, Durham, NC, U.S.A.
4. Pathology, Duke Medical Center, Durham, NC, U.S.A.
5. Preston Robert Tisch Brain Tumor Center, Duke Medical Center, Durham, NC, U.S.A.
6. Neurobiology, Duke Medical Center, Durham, NC, U.S.A.
7. Neurosurgery Section, Durham VA Medical Center, Durham, NC, U.S.A.