[1] Dana Farber Canc Inst, Dept Adult Oncol & Biostat, Boston, MA 02115 USA
[2] Brigham & Womens Hosp, Dept Radiat Therapy, Boston, MA USA
[3] Harvard Univ, Sch Med, Dept Med, Boston, MA USA
[4] Harvard Univ, Sch Med, Dept Radiat Oncol, Boston, MA USA