[1] ECOG ACRIN Canc Res Grp, Philadelphia, PA 19103 USA
[2] Four Penn Ctr, NRG Oncol, Philadelphia, PA USA
[3] Childrens Oncol Grp, Monrovia, CA USA
[4] Canadian Canc Trials Grp, Kingston, ON, Canada
[5] SWOG Canc Res Network, Portland, OR USA
[6] Alliance Clin Trials Oncol, Rochester, MN USA