[1] Univ Penn, Philadelphia, PA USA
[2] Harvard Univ, Cambridge, MA USA
[3] Univ Philippines, Manila, Philippines
[4] Philippine Inst Dev Studies, Manila, Philippines
[5] NYC Hlth Hosp Elmhurst, Queens, NY USA
[6] Univ Rochester, Rochester, NY USA
[7] Univ Pittsburgh, Pittsburgh, PA USA
[8] Stanford Univ, Sch Med, Palo Alto, CA USA
[9] Mem Sloan Kettering Canc Ctr, New York, NY 10065 USA
[10] Univ Southern Calif, Los Angeles, CA USA
[11] MD Anderson Canc Ctr, Dept Radiat Oncol, Houston, TX 77030 USA