1. National Cancer Center Hospital East, Chiba, Japan;
2. The University of Texas MD Anderson Cancer Center, Houston, TX;
3. Indiana University School of Medicine, Indianapolis, IN;
4. Merck & Co., Inc., Kenilworth, NJ;
5. Merck & Co., Inc., Rahway, NJ;
6. Institut de Cancérologie de l'Ouest, Nantes, France;