1. Division of Urology, McGill University Health Center, Montreal, Quebec, Canada
2. Division of Urology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
3. Department of Pathology, University of Texas M. D. Anderson Cancer Center, Houston, Texas
4. Department of Genitourinary Medical Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas
5. Department of Urology, University of Texas M. D. Anderson Cancer Center, Houston, Texas