HDS Plus PBPC Transplant Vs 4 More Courses of FrontLine Therapy in Pts With Aggressive NHL in PR After Induction Therapy

Inclusion Criteria: * Newly diagnosed, untreated patients with histologically documented aggressive lymphoma; * Age between 18 and 65 years; * Clinical stage at diagnosis: I A bulky - IV B; * Reduction of tumoral masses, after four courses of induction therapy, between 50 and 75%; * Serum negativity for HIV, HbsAg and HCV; * ECOG performance status 0 through 4; * Adequate bone marrow function; * Adequate renal and hepatic functions; * Left ventricular ejection fraction (LVEF) \> 50%; * No previous malignant disease; * No previous chemo-radiotherapy; * No cerebral or CNS involvement, assessed by clinical history, physical examination and CSF examination through lumbar puncture; * Written informed consent given at time of randomization. Exclusion Criteria: * Clinical stage I no bulky, or CS IIA-B with less than three sites of disease involved; * Patients with CR, unconfirmed complete remission (uCR), very good PR (\>75%) and clinical response less than 50%, as defined by Cheson et al., following four courses of induction therapy; * Tumor involvement of CNS (except patients with peridural masses without liquor involvement , who can be enrolled in this study); * Indolent lymphoma transformed in more aggressive histologic type, even if never previously treated; * Aggressive non-Hodgkin's lymphoma in pre-transplanted patient; * Clinically significant secondary cardiovascular disease e.g. uncontrolled hypertension, (resting diastolic blood pressure \> 115 mmHg), uncontrolled multifocal cardiac arrhythmias, symptomatic angina pectoris or congestive cardiac failure NYHA class III-IV; * Left ventricular ejection fraction (LVEF) \< 50%; * Evidence of any severe active acute or chronic infection; * Concurrent malignancy of history of other malignancy, except basal cell carcinoma of the skin (BCC) and in situ cervical carcinoma (CIN); * myelodisplastic syndrome; * HbsAg, HIV-positive, or HCV-RNA-positive patients; * Patient with psychiatric, or any disorder that compromises ability to give truly informed consent for participation in this study; * Pregnant woman; potential child-bearing women can be enrolled if adequate contraceptive precautions are used before entering this trial and for the duration of the trial; * Concerns for patient's compliance with the protocol procedures.