Inclusion criteria:

• Previously untreated patients with newly diagnosed peripheral T-cell lymphoma of stage I bulk (≥ 7.5 cm) and stages II to IV.
• Patients with a confirmed histologic diagnosis of peripheral T-cell NHL according to the WHO classification:
• Peripheral T-cell lymphoma, unspecified (PTCL NOS)
• Angioimmunoblastic T-cell lymphoma
• Enteropathy-type T cell lymphoma
• Subcutaneous panniculitis-like T-NHL (gamma-delta T-cell lymphoma)
• Hepatosplenic T-cell lymphoma
• Extranodal NK/T cell lymphoma, nasal type
• Age 18-60 years at time of randomization
• Life expectancy of 3 months or longer
• ECOG performance status (PS) 0, 1 or 2 at the time of randomization. However, PS 3 will be acceptable if lymphoma-related.
• Measurable disease (defined as at least one lesion with two measurable perpendicular diameters of which at least one should be >= 15 mm).
• Written informed consent

Exclusion Criteria:

• Patients with NK/T-NHL of the following type:
• Precursor T cell lymphoblastic lymphoma/leukemia
• All mature T cell leukemias (T-PLL, ATLL, NK cell leukemia, T-LGL, HTLV1-pos ATL)
• Alk-positive and negative anaplastic large cell lymphoma
• Blastic NK cell lymphoma
• Cutaneous T-cell lymphoma, transformed or not
• Concurrent severe and/or uncontrolled medical disease (e.g. uncontrolled diabetes, congestive heart failure, myocardial infarction within 6 months prior to the study, unstable and uncontrolled hypertension, chronic renal disease, or active uncontrolled infection), which could compromise participation in the study.
• Known hypersensitivity to murine or chimeric antibodies or proteins
• Severe cardiac dysfunction (NYHA classification II-IV, Appendix H) or LVEF < 45 %
• Significant renal dysfunction, i.e. serum creatinin >2 times upper normal level (UNL), unless related to NHL
• Significant hepatic dysfunction (total bilirubin >2 times UNL or transaminases >= 2.5 times UNL), unless related to NHL
• Impaired pulmonary functions; in this case, the patient is to be excluded if the resultant pulmonary function test shows FEV1<50% or a diffusion capacity <50% of the reference values
• Suspected or documented Central Nervous System involvement by NHL
• Patients known to be HIV-positive
• Patients with active, uncontrolled infections, especially known seropositivity for HCV or HbsAg
• Patients with uncontrolled asthma or allergy, requiring systemic steroid treatment
• Prior treatment with chemotherapy, radiotherapy or immunotherapy for this lymphoma, except local radiotherapy in case of extranodal NK/T cell lymphoma, nasal or nasal type
• History of active cancer during the past 5 years, except basal carcinoma of the skin or stage 0 cervical carcinoma
• Unwillingness or inability to comply with the protocol
• Simultaneous participation in any other study protocol
• Pregnant and nursing women (Women of childbearing potential should use safe anticonceptives) Contraceptive pills, intrauterine devices, injection of prolonged gestagen, subdermal implantation, hormonal vaginal devices and transdermal patches are considered as safe contraceptive methods).