[1] Christie NHS Fdn Trust, Dept Med Oncol, Wilmslow Rd, Manchester M20 4BX, Lancs, England
[2] Univ Manchester, Inst Canc Sci, Wilmslow Rd, Manchester, Lancs, England
[3] Harvard Med Sch, Massachusetts Gen Hosp, Canc Ctr, 55 Fruit St, Boston, MA 02114 USA
[4] Univ Manchester, Fac Med Biol & Human Sci, Rumford St, Manchester, Lancs, England