[1] Canc Registry Norway, Inst Populat Based Canc Res, Post Box 5213, N-0304 Oslo, Norway
[2] Univ Oslo, Inst Basic Med Sci, Oslo, Norway
[3] Romanian Canc Soc, Cluj Napoca, Romania
[4] Folkhalsan Res Ctr, Genet Epidemiol Grp, Helsinki, Finland
[5] Univ Oslo, Inst Hlth & Soc, Oslo, Norway
[6] Univ Med & Pharm Iuliu Hatieganu, Cluj Napoca, Romania
[7] Inst Oncol Prof Dr Ion Chiricuta Cluj Napoca IOCN, Cluj Napoca, Romania
[8] Univ Southern Calif, Dept Prevent Med, Los Angeles, CA USA
[9] Univ Tromso, Fac Hlth Sci, Dept Community Med, Tromso, Norway
[10] Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden