1. Medical Oncology Service, National Cancer Institute, Bethesda, Maryland.
2. Department of Internal Medicine, Sinai Hospital of Baltimore, Baltimore, Maryland.
3. Alvin & Lois Lapidus Cancer Institute, Sinai Hospital of Baltimore, Baltimore, Maryland.
4. Apex Epidemiology, Baltimore, Maryland.
5. Division of Hematology/Medical Oncology, Alvin & Lois Lapidus Cancer Institute, Sinai Hospital of Baltimore, Baltimore, Maryland.