This study evaluates the efficacy and tolerability of treatment for T-lymphoblastic lymphoma (T-LBL) according to a protocol for acute lymphoblastic leukemia. Patients receive one year of intensive cyclical chemotherapy with additional prophylaxis for central nervous system (CNS) relapse by intrathecal therapy and cranial irradiation and mediastinal irradiation after induction chemotherapy.

Inclusion Criteria:

• T-lymphoblastic lymphoma (bone marrow [BM] involvement < 25%)
• Aged 15-65 years (55-65 years if biologically younger)
• Written informed consent

Exclusion Criteria:

• Severe complications due to lymphoma or secondary disease
• T-LBL as second malignancy or other active second malignancy
• Cytostatic pretreatment of LBL (exception of emergency treatments)
• Pregnancy
• Severe psychiatric illness or other circumstances which may compromise cooperation of the patient or informed consent
• Participation in other study interfering with study treatment