1. Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC V5Z 4E6, Canada
2. Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
3. Department of Medicine/Medical Oncology, Duke University School of Medicine, Durham, NC 27710, USA
4. Division of Oncology, Saint Luke's Cancer Institute, Kansas City, MO 64111, USA
5. Pfizer Inc., New York, NY 10017, USA