[1] European Inst Oncol, Clin Pharmacol & New Drugs Dev Div, Dept Med Oncol, I-20141 Milan, Italy
[2] European Inst Oncol, Epidemiol & Biostat Div, I-20141 Milan, Italy
[3] Fdn IRCCS Ist Nazl Tumori, Med Oncol Unit 1, Milan, Italy
[4] European Inst Oncol, Dept Med, I-20141 Milan, Italy