To evaluate outcome and prognosis of patients with T-cell lymphoma we analyzed 343 patients treated within trials of the German High-Grade Non-Hodgkin Lymphoma Study Group (DSHNHL). Two hundred eighty-nine patients belonged to 1 of the 4 major T-cell lymphoma subtypes: anaplastic large cell lymphoma (ALCL), anaplastic large cell lymphoma kinase (ALK)-positive (n = 78); ALCL, ALK-negative (n = 113); peripheral T-cell lymphoma, unspecified (PTCLU; n = 70); and angioimmunoblastic T-cell lymphoma (AITL; n = 28). Treatment consisted of 6-8 courses of CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone/prednisolone) or etoposide plus (CHOEP). Three-year event-free survival (EFS) and overall survival were 75.8% and 89.8% (ALK-positive ALCL), 50.0% and 67.5% (AITL), 45.7% and 62.1% (ALK-negative ALCL), and 41.1% and 53.9% (PTCLU), respectively. The International Prognostic Index (IPI) was effective in defining risk groups with significantly different outcomes. For patients, ≤ 60 years with lactate dehydrogenase ≤ upper normal value (UNV), etoposide improved improved 3-year EFS: 75.4% versus 51.0%, P = .003. In patients > 60 years 6 courses of CHOP administered every 3 weeks remains the standard therapy. Patients with ALK-negative ALCL, PTCLU, or AITL presenting with IPI > 1 have a poor prognosis and should be considered candidates for novel treatment strategies.