[1] UNIV TEXAS, MD ANDERSON HOSP & TUMOR INST,CTR CANC,MED CTR, DEPT MED, HOUSTON, TX 77030 USA
[2] UNIV TEXAS, MD ANDERSON HOSP & TUMOR INST,CTR CANC,MED CTR, DEPT DIAGNOST RADIOL, HOUSTON, TX 77030 USA
[3] UNIV TEXAS, MD ANDERSON HOSP & TUMOR INST,CTR CANC,MED CTR, DEPT PATHOL, HOUSTON, TX 77030 USA
[4] WASHINGTON UNIV, SCH MED, DIV RADIAT ONCOL, ST LOUIS, MO 63110 USA