[1] Ist Ric Farmacol Mario Negri, I-20156 Milan, Italy
[2] Ctr Riferimento Oncol, SOC Epidemiol & Biostat, I-33081 Aviano, PN, Italy
[3] Univ Lausanne, Lausanne, Switzerland
[4] CHU Vaudois, Unite Epidemiol Canc, Inst Med Sociale & Prevent IUMSP, CH-1011 Lausanne, Switzerland
[5] Policlin Monza, Dipartimento Gastroenterol & Nutr Clin, Monza, Italy
[6] Ist Nazl Tumori, Fdn G Pascale, Dipartimento Epidemiol, Naples, Italy
[7] Int Agcy Res Canc, F-69372 Lyon, France
[8] Univ Milan, Ist Stat Med & Biometria GA Maccacaro, Milan, Italy
[9] CHU Vaudois, Registre Vaudois Tumeurs, Inst Med Sociale & Prevent IUMSP, CH-1011 Lausanne, Switzerland