1. From the Urology Section (RBA, MK) and Department of Pathology (AAB), Veterans Affairs Health Care System and Department of Pathology (DLM) and Division of Urology (RBA, ENK, JK), University of Maryland School of Medicine, Baltimore and C. W. Bill Young DOD Marrow Program, Georgetown University (MF-V), Kensington, Maryland, and Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine (KJP), Philadelphia, Pennsylvania