[1] Univ Hosp Cologne, Dept Internal Med 1, Cologne, Germany
[2] Univ Hosp Cologne, German Hodgkin Study Grp, Cologne, Germany
[3] Univ Kiel, Univ Hosp Schleswig Holstein, Hematopathol Sect, Dept Pathol, Kiel, Germany
[4] Univ Groningen, Univ Med Ctr Groningen, Dept Pathol & Med Biol, Groningen, Netherlands
[5] Univ Hosp Cologne, Ctr Mol Med, Cologne, Germany
[6] Univ Cologne, Else Kroner Forsch Kolleg Cologne, Cologne, Germany