[1] Ist Ric Farmacol Mario Negri, Dept Epidemiol, I-20156 Milan, Italy
[2] Ctr Riferimento Oncol, Serv Epidemiol & biostat, I-33081 Aviano, PN, Italy
[3] Int Agcy Res Canc, F-69372 Lyon, France
[4] Ist Tumori Fdn Pascale Cappella dei Cangiani, Naples, Italy
[5] Ist Regina Elena Studio & la Cura Tumori, Serv Integrat Epidemiol & Sist Informat, I-00161 Rome, Italy
[6] Univ Milan, Ist Stat Med & Biometria, I-20122 Milan, Italy