The following institutions participated in this study: University of Oklahoma, Oklahoma, OK–Howard Ozer, MD, supported by CA37447; Christiana Care Health Services, Inc Community Clinical Oncology Program (CCOP), Wilmington, DE–Stephen Grubbs, MD, supported by CA45418; Dana-Farber Cancer Institute, Boston, MA–Eric P. Winer, MD, supported by CA32291; Duke University Medical Center, Durham, NC–Jeffrey Crawford, MD, supported by CA47577; Evanston Northwestern Healthcare CCOP, Evanston, IL–Gershon Y. Locker, MD; Georgetown University Medical Center, Washington, DC–Minetta C. Liu, MD, supported by CA77597; Grand Rapids Clinical Oncology Program, Grand Rapids, MI–Marianne Lange, MD; Greenville CCOP, see above Cancer Center of Carolinas; Hematology-Oncology Associates of Central New York, Syracuse, NY–Jeffrey Kirshner, MD, supported by CA45389; Illinois Oncology Research Association, Peoria, IL–John W. Kugler, MD, supported by CA35113; Kansas City Community Clinical Oncology Program CCOP, Kansas City, MO–Jorge C. Paradelo, MD; Massachusetts General Hospital, Boston, MA–Michael L. Grossbard, MD, supported by CA12449; Missouri Baptist Medical Center, St. Louis, MO–Alan P. Lyss, MD, supported by CA114558-02; Missouri Valley Cancer Consortium, Omaha, NE–Gamini S. Soori, MD; Mount Sinai Medical Center, Miami, FL–Rogerio Lilenbaum, MD, supported by CA45564; Mount Sinai School of Medicine, New York, NY–Lewis R. Silverman, MD, supported by CA04457; Nevada Cancer Research Foundation CCOP, Las Vegas, NV–John A. Ellerton, MD, supported by CA35421; New Hampshire Oncology-Hematology PA, Hooksett, NH–Douglas J. Weckstein, MD; Northern Indiana Cancer Research Consortium CCOP, South Bend, IN–Rafat Ansari, MD, supported by CA86726; Rhode Island Hospital, Providence, RI–William Sikov, MD, supported by CA08025; Roswell Park Cancer Institute, Buffalo, NY–Ellis Levine, MD, supported by CA02599; Southeast Cancer Control Consortium Inc. CCOP, Goldsboro, NC–James N. Atkins, MD, supported by CA45808; State University of New York Upstate Medical University, Syracuse, NY–Stephen L. Graziano, MD, supported by CA21060; The Ohio State University Medical Center, Columbus, OH–Clara D. Bloomfield, MD, supported by CA77658; University of California at San Diego, San Diego, CA–Joanne Mortimer, MD, supported by CA11789; University of California at San Francisco, San Francisco, CA–Alan P. Venook, MD, supported by CA60138; University of Chicago, Chicago, IL–Gini Fleming, MD, supported by CA41287; University of Illinois MBCCOP, Chicago, IL–Lawrence E. Feldman, MD, supported by CA74811; University of Iowa, Iowa City, IA–Gerald Clamon, MD, supported by CA47642; University of Maryland Greenebaum Cancer Center, Baltimore, MD–Martin Edelman, MD, supported by CA31983; University of Massachusetts Medical School, Worcester, MA–William V. Walsh, MD, supported by CA37135; University of Minnesota, Minneapolis, MN–Bruce A. Peterson, MD, supported by CA16450; University of Missouri/Ellis Fischel Cancer Center, Columbia, MO–Michael C. Perry, MD, supported by CA12046; University of Nebraska Medical Center, Omaha, NE–Anne Kessinger, MD, supported by CA77298; University of North Carolina at Chapel Hill, Chapel Hill, NC–Thomas C. Shea, MD, supported by CA47559; University of Texas Southwestern Medical Center, Dallas, TX–Debasish Tripathy, MD; Wake Forest University School of Medicine, Winston-Salem, NC–David D. Hurd, MD, supported by CA03927; Washington University School of Medicine, St. Louis, MO–Nancy Bartlett, MD, supported by CA77440; and Western Pennsylvania Cancer Institute, Pittsburgh, PA–Richard K. Shadduck, MD.