[1] Univ Hosp Gasthuisberg, B-3000 Louvain, Flemish Brabant, Belgium
[2] Cent Univ Hosp Asturias HUCA, Oviedo, Spain
[3] Ctr Hosp Univ Robert Debre, Reims, France
[4] Univ Helsinki, Cent Hosp, Helsinki, Finland
[5] Inst Cancerol Ouest, Nantes, St Herblain, France
[6] Hop St Antoine, F-75571 Paris, France
[7] Serv Oncol Med HC, Madrid, Spain
[8] Hosp Univ Miguel Servet, Zaragoza, Spain
[9] Canc Ctr Reutlingen, Reutlingen, Germany
[10] III Med Univ Klin Salzburg, Salzburg, Austria
[11] Kantonsspital Graubuenden, Chur, Switzerland
[12] Genentech Inc, San Francisco, CA 94080 USA
[13] F Hoffmann La Roche & Co Ltd, CH-4002 Basel, Switzerland
[14] Univ Canc Ctr Hamburg UCCH, Hubertus Wald Tumor Ctr, Hamburg, Germany