[1] Univ British Columbia, Fac Med, Dept Radiol, Vancouver, BC V5Z 4E3, Canada
[2] Univ British Columbia, Div Med Oncol, Vancouver, BC V5Z 4E3, Canada
[3] Univ British Columbia, Dept Surg, Vancouver, BC V5Z 4E3, Canada
[4] Univ British Columbia, Dept Med, Vancouver, BC V5Z 4E3, Canada
[5] Ronald Regan UCLA Med Ctr, David Geffen Sch Med, Dept Radiol Sci, Los Angeles, CA USA