[1] Univ Hosp Essen, Essen, Germany
[2] Ist Nazl Tumori Fdn Pascale, Naples, Italy
[3] Univ Autonoma Madrid, Hosp Univ La Paz, Madrid, Spain
[4] Netherlands Canc Inst, Amsterdam, Netherlands
[5] Bristol Myers Squibb, Munich, Germany
[6] Mt Vernon Canc Ctr, London, England