[1] Queens Univ, Canada Clin Trials Grp, Natl Canc Inst Canada, Kingston, ON K7L 3N6, Canada
[2] Med Sch Newcastle Upon Tyne, No Inst Canc Res, Newcastle Upon Tyne NE2 4HH, Tyne & Wear, England
[3] NCI, Med Oncol Branch, Bethesda, MD 20892 USA
[4] NDDO Res Fdn, Amsterdam, Netherlands